Understanding baby leaps in mental development

Research spanning over 35 years into the development of babies has found that all normal and healthy babies go through predictable phases of fussiness. These difficult phases, called ‘the wonder weeks’, can lead parents to despair. Babies cry more, become clingier, and crankier (what the Wonder Weeks authors describe as the three Cs), but there is a good reason for this.

A baby’s brain undergoes sudden and drastic changes, which alters the way they perceive the world. This can be frightening and confusing for them, but these brain changes are a sign of progress. Your baby is learning new skills, so as challenging as these periods are, they are temporary and cause for celebration.

Understanding these leaps and being prepared for a fussy baby will help you cope through these times, and give you the tools to support them through it when they need it.

Signs that your baby is going through a leap

  • Crying real tears for the first time or crying more often
  • Staying awake for longer periods, many overnight wakings, or nap refusal
  • Increased alertness
  • You might notice they become shy around strangers, and cling to you more
  • More demanding for attention again
  • They may seem quieter or less lively than usual
  • Their appetite is reduced, or they’re fussing at the breast or bottle
  • They might show a caregiver preference
  • They’re starting to show signs of boredom and expect to be amused more

What’s happening during these ‘wonder weeks’

Your baby is going through a period of huge and rapid sensory, cognitive, physical, and emotional growth and development. It’s normal, healthy, and to be expected.

How to support baby through a leap

Some of these big changes can make them feel confused and bewildered so they need time to adjust, so to help them:

  • Having plenty of close physical contact helps to calm some babies. You are their secure base, and they need to feel safe before they want to discover the world again with the help of their new skills.
  • Show your baby things around the house at different distances, offer variety in toys, views, and sounds (you might notice they start to get bored now), help them discover their hands and feet, encourage them to grab toys, and encourage and respond to sounds they make.
  • Experiment to see which activities they enjoy and allow opportunities for independent play
  • Chat with them often, and let their responses guide you. Here is how to recognise and respond to newborn cues.
  • Encourage them to practice new skills, to use their new voice (you might hear high-pitched shrieks), chat with them, respond to their communication attempts, teach your baby to reach and grasp toys, allow them to play without clothes on, and encourage them to roll.

After the leap

You might find your baby to be more cheerful, easygoing, and alert. They also might not demand as much attention as before, becoming more independent. Your baby will emerge from these fussy periods with a new skill or several new skills. You might not notice these skills, or they may be fleeting, but an immense amount of development and change is happening for your little one. Remember that these wonder weeks are positive and necessary.

Note: If you feel exhausted, worried, exasperated, and overwhelmed during these fussy phases, trust your instincts and ignore advice to be stern or to sleep train your baby. The best thing you can do is comfort your baby. If you’re struggling, please speak to a professional or get some in-home support if possible.

Hetty van de Rijt, PhD, Frans X. Plooij, PhD, & Xaviera Plas-Plooij, The Wonder Weeks – A Stress-Free Guide to Your Baby’s Behavior, The Countryman Press, USA, 2019.