Your Baby at 4 Months: Laughs, Rolling and the Sleep Shake-Up

What your baby is doing

By 4 months, the CDC lists milestones like:

• Smiling on their own to get your attention, and chuckling (not quite laughing yet for every baby).
• Turning toward the sound of your voice.
• Holding their head steady without support when being held.
• Holding a toy when you put it in their hand, swinging at toys, and bringing hands to mouth.
• Pushing up onto elbows or forearms during tummy time.

Some babies roll from tummy to back around now. Rolling back to tummy usually follows later.

The sleep shake-up

Many parents notice sleep getting worse somewhere between 3 and 5 months, often nicknamed the “4-month sleep regression.” Babies’ sleep cycles are maturing, so they wake more often between cycles and may need help settling. What helps:

• A consistent bedtime routine (same order, every night).
• Drowsy but awake at bedtime, so the baby practices falling asleep in the crib.
• A dark room and white noise at a modest volume.
• Patience. It usually settles.

Stop swaddling at the first sign of rolling

This one matters. The AAP says to stop swaddling when the baby starts showing signs of trying to roll, because a swaddled baby who rolls onto their stomach can’t push up. The 2022 AAP safe sleep policy also advises against weighted swaddles and sleep sacks. Move to a regular wearable blanket with the arms free.

Once a baby can roll both ways on their own, you don’t need to flip them back if they roll in their sleep, but always put them down on their back.

Play that builds skills

• Reach games: a toy just out of reach during tummy time.
• Rolling help: gently guide hips and shoulders through a roll during floor play.
• Back-and-forth “conversations”: pause after you talk so your baby can coo back.

The 4-month checkup

Expect growth checks, development questions and recommended vaccines. Good questions to bring: how sleep is going, when to start solids, and whether your baby’s feeding amounts are on track.