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Why Is My Baby Suddenly Not Sleeping? Understanding the Wonder Weeks.

This post may contain affiliate links.

by Carolyn 26 Comments

I remember how excited I was my twins started sleeping through the night. I felt like a mom rock star! Sleep deprivation? Ha! I had conquered bedtime and I was feeling amazing! But, you know how people say not to jinx a good thing? Well, I met my match when my boys turned four months old and hit the wonder weeks. All those nights of lovely sleep? Gone. We were back to square one.

I called my friend, an infant sleep consultant, and cried tears of frustration. I had done everything the books told me to do. I’d swaddled, I’d rocked, I’d nursed, I’d held…and it was like none of that had ever even happened. What had I done wrong? And, more importantly, how could I fix it?

what are the wonder weeks | how to get through the wonder weeks | wonder week | wonder weeks | the wonder weeks

After calming me down, my friend explained that it wasn’t anything I had done or hadn’t done. I hadn’t jinxed it by feeling amazing about our earlier success. Instead, my boys were simply going through one of the “wonder weeks” and this too would pass.

The Wonder Weeks

Despite all of the reading and research I’d done about infant sleep training, I hadn’t heard of wonder weeks. What I discovered left me feeling both reassured and, truth be told, a little intimidated about what was in store for us in the coming year. Now, looking back on that time, I can confidently say that knowledge of the wonder weeks made them much less stressful and gave me hope throughout my boy’s sleep training process.

If you’re new to the concept of wonder weeks, let me explain what they are, why it’s important to understand them, and when they occur. It’s hard being a new parent, but knowing about the wonder weeks can completely change the way you handle your child’s sleeping routine.

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What Are The Wonder Weeks?

The Wonder Weeks idea is based off of research done by Dr. Hetty van de Rijt and Dr. Frans Plooij that proved that infants and toddlers go through 10 different developmental phases with major changes, or “leaps” during the first 20 months of their lives.

The Wonder Weeks are those predictable stages that can cause changes in sleep patterns, behavior, health, and development. Researchers also found that children were more likely to display more of the “three C’s” (crying, clinging, and crankiness) during those time periods. You can read more about the weeks in The Wonder Weeks book; it’s eye-opening!

Why Is It Important to Understand the Wonder Weeks?

Imagine feeling like you are the worst parent in the world, because your child is being cranky and clingy. You’re sleep deprived and, despite your best efforts, the tricks you’ve tried in the past for sleep training are now not working. I know how horrible it is to feel that way – and that’s why understanding the idea of the wonder weeks was such a relief.

Instead of feeling like I was failing at motherhood, I was able to match my child’s age with the developmental leap he was currently taking. Growing is hard and infants and toddlers don’t have many ways to express their feelings other than through the three C’s. It wasn’t that I was doing anything wrong at all; my child was just growing. It was a moment of clarity and utter relief.

The 10 Major Wonder Weeks

Here is a brief outline of the 10 basic time frames that children predictably experience the leaps in growth. If you’re experiencing a significant amount of crying, clinginess, and crankiness with your child, you’ll most likely find his age below!

Approximate Weeks When Leaps in Development Occur

  • 4-5 Weeks: The World of Changing Sensations
  • 8-9 Weeks: The World of Patterns
  • 11-12 Weeks: The World of Smooth Transitions
  • 18-19 Weeks: The World of Events
  • 25-26 Weeks: The World of Relationships
  • 36-40 Weeks: The World of Categories
  • 45-46 Weeks: The World of Sequences
  • 54-55 Weeks: The World of Programs
  • 63-64 Weeks: The World of Principles
  • 74-75 Weeks: The World of Wonder

 

The Wonder Weeks book breaks down the developmental phases into a lot more detail and provides a great deal of insight. I strongly encourage you to pick up a copy to have on hand. I referred to mine throughout the toddler years and it’s one of my favorite books to give at baby showers!

How to Get Through the Wonder Weeks

Understanding that this was normal and just a phase that we would get through helped me tremendously. Knowing there is an end in a few days can really help with my patience.

  1. While keeping as close as you can to your routine be a little more flexible with holding, feeding and rocking.
  2. This isn’t the time to try sleep training or make a major change to your baby’s routine.
  3. Baby wear a little more often. The baby carrier is your friend.
  4. I found marking a date 7 days in advance that I would tell my husband (and myself) that we just had to make it to that date. Having an end date in mind helped us be patient. We normally found that we would forget about that date because it would end before the date would come.

For me, understanding that my child’s behavior and sudden, inconsistent sleep patterns were indicative of a milestone that he was reaching made the long nights bearable. It gave me a frame of reference and a heads-up as to what I could expect in the weeks to come. If nothing else, the wonder weeks idea gave me peace and confidence as a mother. I truly hope it does the same for you.

Want go further with some in depth sleep advice? I recommend the individual and group coaching plans from The Baby Sleep Site. Every child and family has their own patterns and lifestyle and the Baby Sleep Site’s plans can be made to adjust to your needs. They also have DIY monthly plan options if you don’t want the individual sleep coaching (or it doesn’t fit your budget).

The Baby Sleep Site has worked with over 35,000 moms and Nicole Johnson, the founder, has made it her mission to help tired parents solve their babies’ sleep challenges in a manner that fits your child’s personality and your parenting style. Check it out here today.

When to start sleep training | Baby Sleep Site

Other sleep articles:

Dream Feed 101: What It Is, How to Do It, and Why It May Help Your Baby Sleep Through the Night

and

When To Start Sleep Training: It’s Not Too Late!

Like it? Pin it!

what are the wonder weeks | how to get through the wonder weeks | wonder week | wonder weeks | the wonder weeks

what are the wonder weeks | how to get through the wonder weeks | wonder week | wonder weeks | the wonder weeks

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Filed Under: Baby's First Year

Comments

  1. Gingermommy says

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    This is a wonderful and information filled post. I love that you have shed some light on the wonder weeks. I am sure there are many that I don’t know about them.

    Reply
  2. robin rue says

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    I was blessed with 2 great sleepers. My boys both started sleeping through the night at 12 weeks and never looked back 🙂

    Reply
  3. Melissa Chapman says

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    It is so nice when the baby finally sleeps through the night for some it happens after a few weeks, for others like me, it took years. Every child is different and those hints are helpful.

    Reply
  4. Joanna @ Everyday Made Fresh says

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    I was so thankful that both of my girls loved to sleep when they were babies. My youngest is now 12, and having a hard time sleeping through the night. :-/

    Reply
  5. Angela Tolsma says

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    I have never heard of wonder weeks what an interesting theory though! Babies grow so fast it makes sense that their systems would be changing and it would cause it’s during that time especially when sleeping.

    Reply
  6. Ana De- Jesus says

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    I did some studies on Child Development when I was younger and I had no idea that there was such thing as wonder weeks, but having varying developmental stages completely makes sense! I am so glad that it helped you feel more reassured as a parent hun x

    Reply
  7. Reesa Lewandowski says

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    Oh those wonderful wonder weeks LOL! It’s not easy, especially when you think you finally got things down to a routine.

    Reply
  8. Krystel | Disney on a Budget says

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    This was wonderful to read because I have never heard of this and now I can help people. I will be there at some point in my life

    Reply
  9. Karen Morse says

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    It’s good for parents to learn more about this so that they won’t feel like they’re doing anything wrong. Of course the babies are all different but it’s nice to get an idea of what’s happening.

    Reply
  10. Toya says

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    Thank you for this information I have never heard of the Wonder Weeks before I will definitely pass this information along to friends that are new moms and book mark this for myself when it is my turn.

    Reply
  11. Beth Davidson says

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    I read about these weeks all the time, but I’m not sure why… My kids never sleep! My two year old still wakes up every couple nights and my six month old is super needy. So, on the one hand I don’t have to worry about the wonder weeks, but on the other… Dang I’m tired. 🙂

    Reply
  12. Rachel says

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    I know that my kids went through those stages, but I didn’t know that there was a book on them. I would recommend new parents check it out.

    Reply
  13. serena says

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    I haven’t heard of the wonder weeks. Thanks for sharing, I’ll definitely share this with some friends that have newborns.

    Reply
  14. Jewish Chick says

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    My daughter didn’t sleep through the night until she was 13 months old. There were mothers all around me praising their little angels who did 10 hour stretches at 4 months old. Fast forward 5 five years and my daughter easily can do 12-13 hours straight while there kids are in and out of their beds 2-4 times a night. #karma

    Reply
  15. Krystal Butherus says

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    I love this post for the information content! Some of these could have been why our son wasn’t the best sleeper.

    Reply
  16. Terri Steffes says

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    I loved learning about the Wonder Weeks. I haven’t heard of this research but now I want to know more!

    Reply
  17. Louise says

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    Such an insightful post, I know it will be a great help for my friend who has recently had her first baby!

    Reply
  18. Elise @ Belle Meets World blog says

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    Wow thanks for sharing about the wonder weeks – who knew!? I’m going to share this with my colleague who is struggling with the ‘why isn’t my baby sleeping??’ issue right now! Thanks so much and Happy New Year!

    XO
    Elise @ Belle Meets World blog

    Reply
  19. Censie Sawyer says

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    Great tips for parents with babies. This age can be difficult when it comes to sleeping. Everything is a stage though, embrace the moments you have.

    Reply
  20. Jessica Joachim says

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    This is so helpful to new parents.! So many times new parents don’t know why the baby stops sleeping at some point, but like you said, it is a phase and will eventually pass.

    Reply
  21. Maria says

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    This is so interesting! I had never heard of the concept of Wonder Weeks before. It’s easy to forget how much is NEW to a newborn, so it’s no surprise that that novelty would interrupt their sleep!

    Reply
  22. Melissa says

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    I had no idea about Wonder Weeks, but it definitely makes sense. My one year old needs a lot of rocking through the night, but I have a pretty constant routine.

    Reply
  23. kimberly lewis says

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    this is so interesting. it’s hard enough to be a parent. It really helps when you can find answers for different behaviors!

    Reply
  24. Tiffany Haywood says

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    Why oh why did I not have this information when my Kiddies were babies. This is really interesting.

    Reply
  25. Britt says

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    Sleep stuff is always the hardest when it comes to kids. All three of my kids were all different with it too.

    Reply
  26. Heather says

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    This makes great sense! My oldest daughter is now nine but was never a great sleeper. Our second is two year old and was sleeping through the night at just four months old. They are so different and it’s never fun when your child doesn’t sleep!

    Reply

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Welcome to Fennell Seeds. I am Carolyn Fennell and I have twin boys and a little girl. Do you feel like you are struggling to keep up with your house, life and all the little things? Let's figure out short cuts and helpful tips together. Welcome! Read more...

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