Physical Development

Fourth Month

What to Expect

Floor play is essential for the baby to develop arm strength. The baby will be able to hold his chest and head much higher up off of theg ground when lying on their stomach. The baby might be able to roll over both ways. The baby will be able sit propped up and walk with assistance.


The baby will likely become better and more controlled when rolling over as the month continues. Their strength and coordination improves.

How to Help Your Baby

  • Allow your baby play time on the floor to explore
  • Give your baby the opprotunity to sit up while sitting on the floor.
  • Be sure to babyproof the house
  • Never leave the baby unattended
  • Help them to roll by placing their favorite toy by their side to encourage them to reach and then roll over

Milestones During the 4th Month

  • Smile spontaneously, especially at people
  • Like to play with people and might cry when playing stops
  • Copy some movements and facial expressions, like smiling or frowning
  • Begin to babble
  • Babble with expression and copies sounds he hears
  • Cry in different ways to show hunger, pain, or being tired
  • Let you know if she is happy or sad
  • Respond to affection
  • Reach for toy with one hand
  • Use hands and eyes together, such as seeing a toy and reaching for it
  • Follow moving things with eyes from side to side
  • Watch faces closely
  • Recognize familiar people and things at a distance
  • Hold head steady, unsupported
  • Push down on legs when feet are on a hard surface
  • May be able to roll over from tummy to back
  • Can hold a toy and shake it and swing at dangling toys
  • Bring hands to mouth
  • When lying on stomach, pushes up to elbows