Wonder Weeks – Week by Week

wonder-weeks-chartWhen Olivia started behaving “strangely” at 5 weeks, and then again at 7 1/2 weeks, I started researching growth spurts. Obviously, I knew that at this age babies are always evolving and that you can’t count on one period lasting too long (which is great news for us because it means a light at the end of the tunnel for all of this sleep deprivation!) Still, being the compulsive researcher that I am, I just had to figure it out. Imagine my surprise when I stumbled across this book: The Wonder Weeks. OMG, it described pretty much word-for-word what I was going through with O. (extra fussiness, clinginess, change in eating patterns). And it made SO much sense. In a nutshell, the book describes 10 developmental growth spurts known as Wonder Weeks (these are different from physical growth spurts, although the timing of some may coincide). These are periods in which baby is putting so much energy into learning new skills that she starts feeling out of sorts. Wonder Weeks take place at week 5, 8, 12, 19, 26, 37, 46, 55, 65 and 75 and the “stormy”, or fussy periods can last anywhere from a few days to 6 weeks (in the later periods) and are followed by some clear developmental leaps. It’s great knowing what drives the change in behavior – otherwise known as the 3 Cs: clinginess, crankiness, and crying – during the Wonder Weeks but what’s even cooler is witnessing baby’s leaps afterwards!!

Okay, so what exactly happens? Why is my baby acting fussy and clingy, you ask? I highly recommend getting the book because it has a ton more detail and activities to do at each leap, but I’ve put together an outline of the Wonder Weeks below. I will update each time we go through a leap with Olivia. NOTE: To read more about what each phase is like for us, click here.

UPDATE, 2/9/14: Now that Olivia has passed the traditional Wonder Weeks phases, I thought I’d try documenting my observations beyond Wonder Week 75.  Interestingly, the authors agree that Wonder Weeks may even span well into adulthood (think moody teenage years, mid-life crisis, etc.). 

Do you have questions about the Wonder Weeks or want to share your little one’s behavior during these leaps? Leave a comment below!

>>>>>Scroll over to read all columns>>>>>

Wonder Weeks Week by Week
Wonder Week Developmental Milestone Behavior Activities O's Behavior O's Leaps
Wonder Week 5 The World of Changing Sensations: Baby's perceptions of the outside world start changing as she starts sensing more of the stimuli around her. Increased crying; Is clingy and loves skin-to-skin contact; Trouble sleeping (more than usual) Cuddle; Talk and sing; Rock her (the Moby Wrap is our best friend) Started waking more at night; became really fussy in the early evening 6 – 8pm Seemed more aware; Started smiling; Started cooing and gurgling; Displayed preference for bird sounds
Wonder Week 8 The World of Patterns: Baby starts to recognize patterns using all senses. She starts distinguish herself from the world around her. This is a huge paradigm shift. Demands more attention; Increased crying; Is clingy; Decreased appetite; Sucks thumb Engage her senses with bright colors and different sounds (this bright Manhattan Toy wood rattle is perfect) Extremely clingy and fussy at night; Slightly decreased appetite some days; Sucking on hands; Read more here Discovered her hands and love to suck them (favors her left); Gurgles and coos for much longer; Bats at toys; Loves to stare and smile at lights and shadows;
Wonder Week 12 The World of Smooth Transitions: Baby's movements become less jerky; She is able to perceive more nuances in her senses May be quieter than usual; Sleeps poorly; Is clingy; Decreased appetite Focus on sounds; Help baby grab/reach for objects; Help her feel different textures/fabrics (her Jellycat book with different crinkly fabrics is a huge hit) Extremely fussy and clingy during the "witching hour" (5 – 8 pm); Decreased appetite; Read more here and here Rubs head and ears; Touches knees and legs; Plays with voice and makes new sounds; Blows spit bubbles; Pays more attention to books
Wonder Week 19 The World of Events: Baby can now conceptualize sequence of events (grab toy -> inspect toy -> put in mouth) Demands more attention; Increased crying; Is clingy; Mood swings; Needs more head support/slumps head Help her practice rolling from tummy to back; Offer different toys and show her how to use them (the toys on her Skiphop activity mat are especially great because she can bat and grab at them); Play peek-a-boo Extremely fussy; Very clingy; Sleep regression (woke almost hourly at night and napped poorly during the day); Read more here and here Better at sitting up; Grabs at toys with both hands; Pulls bottle to mouth; Responds to "where's mommy/where's daddy" by looking around to find us; Significant improvement in almost all skills
Wonder Week 26 The World of Relationships: Starts to perceive distance between objects (and people); Starts to understand basic cause and effect Demands more attention; Sleeps poorly; Is clingy; Increased crying/crankiness; Dislikes diaper changes Experiment with coming and going; Play variations of peek-a-boo with toys (this Very Hungry Caterpillar hand puppet is just the right size) Had a couple of very cranky days Started officially crawling; shakes rattles to hear sound; likes pressing buttons; "yells" and growls at things she likes
Wonder Week 37 The World of Categories: Baby understands that objects can be categorized into groups (foods/toys) Demands more attention; Sleeps poorly; May cling to your clothes; Acts more babyish; May be quieter than usual Encourage her to imitate gestures; Call baby to you or ask her to pass you an object (the Oball is perfect for her to grip and she also likes the Tiny Love spin ball) Very clingy and more demanding; stranger anxiety; fussy eating; Likes to be held like a baby; Read more here Plays "catch" with ball; is more independent; bangs similar toys together; loves turning pages in books
Wonder Week 46 The World of Sequences: Baby starts recognizing the importance of order and how to put things together Shyer with strangers; Moody; Jealous; Sleeps Poorly; Acts more babyish; May be quieter than usual Provide feedback during exploration (praise or warning if something is dangerous); Point at an object and name it Very clingy and grabs on to my legs; whiny; poor naps for 2-3 days Plays catch with a ball; throws objects from highchair; puts objects in/out of containers (likes an empty oatmeal canister and her Fisher-Price shape sorter); smells flowers and makes "mmmm" sound; Read more here
Wonder Week 55 The World of Programs: Baby's understanding of sequences evolves to understanding of multiple means to an end (different sequences can accomplish the same thing) Moody; Jealous; Sleeps Poorly; Acts more babyish; May daydream; May be mischievous; Loss of appetite Introduce more complex toys (the B. Zany Zoo cube is a gorgeous toy with lots of fun activities); Unpack and put away groceries together (the Earlyears Lil Shopper filled with soft groceries allows baby to mirror your actions) Cries more easily; has had a couple of cranky episodes; is more temperamental and yells when frustrated; clings to our legs and clings to daddy's neck when he tries to put her down; acts extra sweet; throws mini-tantrums Is more independent and adventurous; is joining words together ("mama up"); recognizes sequence of events (bag+keys=walk)
Wonder Week 64 The World of Principles: Baby begins thinking about how to accomplish certain goals; Starts making choices and conceptualizing consequences Wants more physical contact; Is shyer with strangers; Wants to be entertained; Moody; Sleeps poorly; Acts more babyish Make jokes and be silly; Encourage physical antics; Play singing and rhyming games; Practice animal sounds (Fisher-Price The Farmer Says toy is simple and so much fun) Fussy eater; throws temper tantrums in order to get her way; slaps things away if she doesn't want them Mimics domestic routines (O loves grabbing our keys when we go out. These B. Fun Keys are great b/c she isn't fooled by plastic ones); practices happy and sad emotions; vocabulary continues to expand
Wonder Week 75 The World of Systems: Baby can understand and differentiate between systems (her family vs. her friend's family); She understands that she can choose how she wants to behave; Starts to develop notion of self and conscience Is clingy; Is shyer with strangers; Jealous; Moody; Sleeps poorly; Acts more babyish Practice balance; Encourage physical games; Pronounce words differently; Blow bubbles Especially clingy; throws mini tantrums and spits Differentiates between her things and ours; makes up funny voices; speaks in short sentences; loves to pretend; loves to doodle – this B. Toulouse Lap-Trec magnetic drawing board is great for helping develop her motor skills and stimulate her imagination
Wonder Week 82 Is really clingy; Particular about foods and how objects are placed (blocks stacked); Naps poorly Is starting to recall events that took place a few weeks ago (when Dr. gave her lollipop or when we went to the zoo with Abby and Mac)
Wonder Week 98 Is clingy and wants me to hold her a lot more; Cries really hard when throwing mini-tantrums; Fights diaper changes Is starting to understand basic reasoning ("If we don't get dressed now we can't go to the park") 
Wonder Week 126 Practice problem solving and fine motor skills with more complex puzzles and crafts with small self-adhesive foam shapes; Encourage pretend play with a wooden tool box or tea set Potty regression; Wakes up crying 3-4 times per night; Is able to concentrate for longer periods of time Uses imagination to play pretend with more complex scenarios ("I'm only a princess when I wear a princess dress"; gathers all dolls for tea party)

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  1. Hi! I LOVE this…haha, it totally explains why my daughter’s been acting so “interesting” the past few weeks. She must be experiencing the Wonder Week 75 stage and it’s lasting the full 6 weeks. She’s been clingy, moody, and uncharacteristically shy around strangers. It all makes sense now! Thanks 🙂

    • Hi Ali, thanks for stopping by! I absolutely love your blog! I definitely recommend getting the book – less so for Abigail since she’s on her last WW, but for your upcoming addition 🙂 It has a ton of great insight and activities for each of the Wonder Week phases.

  2. Wish I saw this post before I bought the book! Hehe! Yes, being the compulsive researcher I too am, I found this book & downloaded the iPhone app. It described exactly how my girl was when she’s moving on to smooth transitions. It alay my worries brcause just when i thought we were making great progress in terms of wakefulness & interaction, she suddemly became withdrawn & cried a lot and cried very hard like ive mever seen before. Am waiting for the book to arrive in my mail, excited!! 🙂

    • I’m glad this helped! The book definitely has a lot of great activity ideas for each WW, so I still think it’s worth it! Great blog, btw 🙂

    • Great question, April! Yes, they are based on your due date and not your little one’s actual birthdate (unless they were the same :)).

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  4. My daughter is 23 months old and has gone through al her WWs. I’m wondering if there are further developmental time frames that might cause her to have the 3 C’s?

    • Hi Fran, thanks for stopping by! Yes, I read that there are; they just haven’t been studied in depth or documented. It’s believed that we experience these phases well into adulthood (think teenage years, mid-life, etc.). It’s pretty amazing to think about!

  5. Pingback: Wonder Week 12 |
  6. Can’t afford the book, or the app… May God bless you for having this information available for free

  7. Hi there

    Love reading your blog. My bubs is going through wonder week 19 I think. She has completely gone off her feeds. Is this normal or should we be looking at other reasons why she’s doing this? Poor naps, moodiness etc it’s all there but very intense this time around. She also went through the 4 month sleep regression and has very restless sleep from 4-6am.she’s up by 5 and this makes her tired during the day.could this be related to WW?

    Thanks 🙂

    • Thanks so much!! Yep, that sounds just like O’s behavior back then. It was definitely a long phase, lasting a few weeks but afterwards it was like sunlight after a big storm! Hope you get there soon 🙂

  8. My son was born at 36 weeks so do I count from what would be full term (37 weeks) or my due date? Would he be 1 week behind or 4? Thanks!

    • Hi Shawna, thanks for stopping by! You’d use your actual estimated due date so he’ll be 4 weeks behind give or take.

  9. My son was born a day early so that doesn’t really affect anything, but how early can a child experience these wonder weeks. He is a day short of 4 weeks old but seems to be experiencing the first wonder week (wonder week 5). The same behaviors to a T. Coincidence or is he just developing a tad early?

  10. Great info. Thanks my daughter is 14 months and I have definitely been noticing a change in behavior the last three days. She clings to my legs, lost her appetite, always whining and crying and wants me to hold her. Now that I know it’s a wonder week I will be more patient and be there for her to guide her through this time.

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