Chapter 4
Wonder Week 5: Discovering a World of Changing Sensations
Around 5 weeks, babies experience their first major developmental leap as they begin perceiving changing sensations both inside and out. Their increased alertness makes their world seem completely different, causing them to seek comfort and closeness.
You'll know your baby is approaching this leap when she becomes intensely fussy, cries more, and refuses to sleep alone. She'll crave extreme closeness, often calming only when held against your body. This isn't manipulation-it's her way of seeking security during this confusing transition.
After this leap, your baby can perceive more of her world. She might discover her hands and feet, practicing control over her limbs. She may become fascinated by light and shadows, study detailed objects, or experiment with making short bursts of sounds like "ah, uh, ehh." These new abilities would have been impossible before this perceptual shift.
Each baby develops unique preferences during this leap. Some become visually oriented, watching everything with bright eyes. Others focus on sounds, keenly listening to music and voices. Some prefer touch and enjoy physical contact games. These early preferences offer glimpses into your baby's emerging personality.
To support your baby through this leap, provide opportunities to explore her new sensory awareness. Show her interesting objects with bright colors or patterns, talk to her in a high-pitched voice (which babies naturally prefer), and give her plenty of physical contact. Most importantly, respond to her communication attempts-she now uses a wider range of crying and gurgling sounds for different situations.
Around 6 weeks, the leap ends and a period of relative peace begins. Your baby becomes more cheerful, alert, and engaged in looking and listening. Her eyes seem brighter, and she can better express likes and dislikes. Life becomes less complicated as communication improves.
Chapter 5
Wonder Week 8: The World of Patterns
At approximately 8 weeks, your baby makes another significant leap as he begins perceiving simple patterns both in his environment and in his own body. This perceptual shift happens across all senses, not just vision.
Before this leap, your baby's movements were jerky and puppet-like. Now he begins making smoother, more controlled movements. He might discover his hands, watching in fascination as these appendages wave across his vision. He'll examine how his hands move, spread fingers, and make flowing gestures. When attempting to grasp objects, he can only close his hands around items placed near him, not yet reaching for them.
Your baby also becomes fascinated by the sounds he makes, especially explosive sounds created by controlling his vocal cords. These "conversations" teach essential communication skills like turn-taking, listening, and imitating. Respond to every sound your baby makes and imitate them to encourage this development.
Games that help babies explore patterns include giving them freedom to watch their hands and feet, having "cozy chats" where they can see your facial expressions, showing them interesting household objects, playing pull-up games if they can lift their head, and taking baths together where they can experience water movement.
During this transition, your baby will likely become clingier, wanting you completely absorbed with him rather than being content alone. He might become shy with strangers, cling physically when held, and experience sleep disturbances. These behaviors signal the internal changes happening as he struggles to make sense of his new perceptions.
Around 10 weeks, babies typically enter a period of comparative ease. They become more independent, interested in their surroundings, and require less constant attention. Many parents report their babies seem "brighter," "wiser," or "more like a real person" at this stage.
Chapter 6
Wonder Week 12: The World of Smooth Transitions
Around 11-12 weeks, babies undergo their third major developmental leap. While the jerky movements from Week 8 continue transforming into smoother actions, this change extends beyond physical movement. Babies now perceive flowing changes in their environment-voices shifting tone, animals moving across rooms, light gradually dimming.
Their world becomes more organized as they discover constant, flowing transitions around them. This new perception brings both joy and challenge, as nothing seems to stand still anymore. During this transition, babies often become fussier but for a shorter duration than previous leaps-some return to normal after just a day, while others may need a week.
You'll notice your baby reaching more smoothly toward objects, though she still needs help. When she misses, encourage her to try again or make the task easier. As grabbing skills improve, she'll spend about two-thirds of waking hours experimenting with her hands. Enhance her tactile exploration by letting her feel various textures-hard, soft, rough, smooth-while describing the sensations.
Your baby also becomes more physically active, playing with smooth transitions through kicking and arm-waving. Some perform impressive feats like putting toes in their mouths. Give your baby time without clothes in a warm environment to move freely. Some babies attempt to roll over and may need help-let them hold your finger for support.
Games that incorporate smooth, gentle movements work best at this stage: "The Airplane" (lifting baby while making increasing sounds), "The Slide" (sliding baby down your chest), "The Pendulum" (swaying baby side-to-side with clock sounds), and "The Rocking Horse" (bouncing baby on knees).
Between 12 and 13 weeks, another period of comparative calm settles in. Your baby seems noticeably smarter-turning immediately toward sounds, laughing, responding to conversation, and shifting position to see better. She's more cheerful and active, watching everything around her. Family members show more interest in her as a person, and she gains her own place in the family.
Chapter 7
Wonder Week 19: Discovering the World of Events
At around 19 weeks, your baby begins to perceive and experiment with events-short, familiar sequences of smooth transitions. While previously mastering simple transitions, now your baby develops more complex understanding, like reaching for a toy, grabbing it with one hand, shaking it, inspecting it, and putting it in his mouth.
This neurological development enables entirely new skills, from babbling more complex sounds to attempting to roll over and crawl. Your baby is learning that the world consists of objects that continue to exist even when not fully visible.
Your baby becomes noticeably fussier between 14-17 weeks as this developmental leap approaches. The fussy period may last anywhere from 1 to 6 weeks, often around 5 weeks, as she works to master new perceptual skills.
This leap takes a toll on parents. You may feel exhausted from constantly soothing a cranky baby. You might feel trapped by your baby's demands, as if you're in prison with your baby calling all the shots. Remember that while feeling frustrated is normal, this phase is temporary and signals important development.
Your baby now becomes tremendously interested in everything around her, wanting to look at and listen to everything possible. Every toy and household item within reach becomes fascinating. She may push herself forward to explore, becoming less interested in cuddling games.
You can help your baby practice rolling from back to tummy by holding a colorful toy beside her that she'll stretch to reach, causing her to roll. Many babies attempt crawling at this age but struggle with forward motion-some get into position but bounce without moving, others slide backward or go in circles.
Between 20-22 weeks, a period of comparative calm begins. Your baby shows greater independence, exploring surroundings with determination rather than relying solely on you for entertainment. Physically active babies twist, turn, roll, and sometimes crawl to reach desired objects. Most babies become noticeably happier during this time, with improved sleep patterns and more regular routines.
Chapter 8
Wonder Week 26: Understanding Relationships in Space
At approximately 26 weeks, your baby makes another significant leap as he begins to understand relationships between objects in his world. Most notably, he now perceives spatial relationships and distances-a radical and sometimes alarming discovery.
He realizes that desired objects can be out of reach on high shelves, or that you can walk away faster than he can follow. The world suddenly seems enormous, and he feels small within it. This newfound awareness can be frightening, making this period challenging for parents.
Your baby now understands that you can increase the distance between you and potentially leave him behind. This realization frightens him as he feels helpless about controlling this distance. To ease his anxiety, stay closer, give warning before walking away, and continue talking when out of sight.
Allow your crawling baby to freely explore a safe room where he can experience spatial relationships: crawling into, out of, under, over, between, on top of, and through objects. Create exploration opportunities with blankets for hills, box tunnels, sheet tents, and doors to open and close.
Your baby is also discovering relationships between body parts, learning coordination and balance. When held by both hands, babies can walk with balance, even taking steps between furniture. Some may push objects while walking or occasionally take independent steps.
The pincer grip emerges as babies discover the relationship between thumb and forefinger, allowing them to pick up tiny objects. This fine motor development opens new possibilities for exploration and manipulation.
Games that help babies explore relationships include various peek-a-boo and hide-and-seek activities that teach object permanence and separation-return relationships. Talking games, song and movement games, balancing games, and outdoor exploration also support this developmental stage.
After this leap, your baby will show remarkable progress, independence and cheerfulness. Their interests expand dramatically-from outdoor elements like flowers and insects to people. They make more social contact and seem more willing to play games with others.
Chapter 9
Wonder Week 37: Categorizing the World
At around 37 weeks, babies begin to recognize that objects, sensations, animals, and people belong together in categories. This perceptual leap affects all senses and begins with a fussy period starting around 34 weeks, typically lasting 3-6 weeks.
During this time, babies conduct methodical investigations-examining specks from the floor or testing food textures-with serious concentration as they learn to categorize their world. They might discover that certain things are alike-they may look similar, make similar sounds, or taste, smell or feel the same.
Your baby will demonstrate category understanding through various skills: recognizing animals and objects in different forms; distinguishing shapes; showing reactions to things being "dirty" or "fun"; understanding names of objects; comparing things seen directly and through screens; relating more to people with sounds and gestures; imitating others; recognizing people in different circumstances; recognizing emotions like jealousy; comforting toys; exaggerating moods; and switching roles by initiating games.
Your baby needs time and guidance to understand categories. Help by providing opportunities to experiment and play in ways that teach why things belong to certain groups. Follow your baby's lead-some prefer starting with objects, others with people.
Your baby examines entire ranges of characteristics to understand categories-testing if objects bounce, feeling their weight and texture, viewing from different angles. Some babies focus on shapes, tracing perimeters with their fingers. Others explore components of objects, testing different parts to understand how things are assembled.
Mobile babies need space to investigate categories through physical movement. As your baby becomes more dexterous while sitting, standing, crawling, and walking, allow exploration throughout your home. Take your crawler outdoors to woods, beaches, lakes, and parks to experience different environments.
Between 40 and 45 weeks, babies typically enter an easier period lasting 1-3 weeks. They show remarkable progress, independence and cheerfulness. Their interests expand dramatically as they become more communicative, energetic and adventurous.
Chapter 10
Wonder Week 46: Mastering Sequences
At around 46 weeks, babies begin to discover the world of sequences-understanding that actions must happen in a certain order to achieve goals. While previously they excelled at taking things apart, they now attempt to put things together, looking first at how objects connect before trying to stack or assemble them.
This represents a significant cognitive leap as babies can now "put two and two together" and become more conscious of their actions. This developmental leap typically begins around 42 weeks and brings another fussy period lasting 3-7 weeks as babies struggle with the challenge of figuring out how things connect.
During this leap, babies become clingier, wrapping themselves around parents or staying remarkably close. Many become shyer with strangers, burying their faces when new people appear. They seek closer physical contact, holding on tightly and becoming upset when put down. Their attention needs increase dramatically, often demanding their mother's undivided focus.
Around 46 weeks, babies grow calmer and begin developing new skills. They handle toys differently, pay more attention to detail, and understand that actions can follow in sequence. This leap enables babies to recognize and construct sequences across all senses, though each child will focus on different aspects based on their temperament and preferences.
Babies may begin pointing to and naming objects; understanding what goes together; making and using tools; developing new movement patterns; engaging in interactive play; playing hide-and-seek games; copying sequential gestures; helping with household tasks; attempting self-care activities; and developing new feeding skills.
Every baby needs time and support to master new skills. You can help by giving opportunities to experiment with sequences, encouraging successes and consoling failures. Your baby will naturally seek sequences to explore through all senses.
Between 47 and 52 weeks, babies enter a period of comparative ease lasting 1-3 weeks. During this time, babies become noticeably more cheerful and independent. They pay better attention when spoken to, play more calmly and independently, and may even prefer being in their playpen. They appear remarkably older and wiser, truly transitioning into toddlerhood.
Chapter 11
Wonder Week 55: Developing Flexible Programs
Around 55 weeks, your baby begins experiencing the world in terms of "programs." Unlike sequences (which follow the same steps every time), programs are flexible paths to achieve goals. For example, dusting furniture can be done in different orders while still accomplishing "dusting."
This mental leap allows babies to understand complex activities like shopping, cleaning, or getting dressed. The first phase of this leap emerges between 49-53 weeks, with most babies starting the second phase around 55 weeks.
During this developmental leap, babies become noticeably more emotional and clingy. They cry more easily than in previous weeks and want to be near their mothers constantly. Their moods can shift dramatically, playing independently one moment and becoming inconsolably weepy the next.
Around 55 weeks, fussiness diminishes as your baby enters the world of programs. Unlike the previous leap's focus on simple sequences, programs involve making choices at multiple decision points to reach a goal. Your toddler now understands that actions like "eating lunch" involve numerous choices-using hands or spoon, switching between foods, taking drinks-all while remaining part of the same overall program.
Support your toddler's exploration of programs by talking about what they're trying to achieve and how they'll do it. Encourage watching, helping, and independent attempts at carrying out their own programs. When your child shows interest in dressing, eating independently, or mimicking your activities, allow them to try even if messy results follow.
Your child now finds fascination in stories that match their experiences and interests. Whether through television, audio, or your own storytelling, keep narratives simple with basic programs they can follow for about three minutes. Encourage their own storytelling attempts when looking at picture books.
Around 59 weeks, most toddlers become less troublesome than during the fussy period. They're friendlier, more talkative, eager to help, and have fewer tantrums. Their independence and cheerfulness return as they master their new skills, though their mobility and confidence still require supervision.
Chapter 12
Wonder Week 64: Understanding Principles
After mastering programs, your toddler now takes another leap forward into understanding "principles"-starting between 59-63 weeks, with most babies fully entering this phase around 64 weeks. While your child previously followed mechanical routines, they now begin to grasp how to adapt programs to different circumstances.
In this world of principles, your toddler begins thinking about thinking. They complete various "programs" more naturally, start getting on top of things rather than being caught in them, and can create or change approaches. They think ahead, contemplate consequences, make plans, and evaluate them.
Your toddler discovers they can manage their world like adults do. They become possessive of toys and assert their will. By trying different strategies and studying others' reactions, they learn when to be friendly, helpful, aggressive, assertive, careful, or polite.
Your toddler experiments extensively with their body's capabilities in the world of principles. They test what their body can do-how to be quick, slow, careful, funny, or clever. They practice climbing stairs, going down slides, fitting into tight spaces, and testing their strength.
In the world of principles, your toddler becomes increasingly resourceful with games and objects. They insist on feeding themselves and manage well with building toys, rings, and puzzles. They experiment with opening faucets, bottles, and twist-off lids.
Your toddler's dramatic tantrums-screeching, rolling, stamping, and throwing things-stem from frustration when people or objects don't respond as expected. These outbursts can erupt from seemingly minor incidents: not getting immediate attention, being denied something, having play interrupted, or when constructions collapse.
Around 68 weeks (approaching 16 months), most toddlers become less challenging as they integrate their new understanding of principles. Parents notice physical changes-children appear slimmer, more mature-looking-alongside behavioral improvements. They become more self-sufficient with everyday tasks, more confident in the wider world, and generally easier to manage.
Chapter 13
Wonder Week 75: Entering the World of Systems
Around 75 weeks (17 months), your toddler leaps into the world of systems-organized units with interdependent parts functioning as a whole. This leap begins with fussiness around 71 weeks as your child senses her world changing.
She starts seeing herself as a system, understanding family as a system different from others, and applying principles more flexibly. She develops early conscience, stronger self-concept, and recognizes others as separate people with different preferences.
Your toddler's greatest discovery is herself as a system. She realizes she owns her body and can control it. She thinks in terms of "me, me, me" as she explores her physical self-studying toes, naming herself, testing boundaries of touch. She develops bodily control through climbing, jumping, and acrobatics.
Her independence blossoms with self-feeding, potty use, drawing, and helping with chores. Her willpower emerges strongly as she tests limits, defies rules, and makes her own decisions about clothes, activities and personal space. She experiments with lying and making things up, laughing at her newfound ability to manipulate information.
Toddlers begin recognizing the family as a cohesive system and their place within it. They develop strict divisions of parental roles and notice when family members are omitted from conversation. Their understanding of family relationships extends to play, as they incorporate dolls and stuffed animals into family-like scenarios.
Between 17-22 months, toddlers experience explosive language development. They eagerly name everything, combining gestures with words to communicate effectively. Their vocabulary expands daily as they practice pronunciation, often mastering first syllables before complete words.
By 18-20 months, many begin forming simple two or three-word sentences like "Daddy sit me" or "That nice," while others still communicate primarily through single words and gestures. Some even "read" books by telling stories while looking at pictures, and participate in songs by filling in words.
This final leap in the first 20 months lays the groundwork for your child's developing worldview, including conscience, norms and values. These early foundations have far-reaching consequences for their development as they continue growing into childhood and beyond.
