Baby Week 31 Development: What to Expect

14 de octubre de 2025|Poco Koko Team

Speed changes everything. Your 31 week old baby has likely moved past the hesitant, wobbly crawling of a few weeks ago and is now motoring across the room with real purpose. Some babies at this age are already pulling up on furniture and taking those first sideways steps known as cruising. Tiny fingers are getting more precise too -- you may notice your baby using a thumb and forefinger to pick up a single Cheerio or a piece of lint you wish they hadn't found. And then there is the wave. That first little bye-bye wave, sometimes aimed at the right person and sometimes at a lampshade, is one of those moments that stops you in your tracks. Here is what week 31 really looks like and how to support your baby through all of it.

Quick Answer

At 31 weeks (~7.5 months), babies typically crawl with increasing speed and confidence, may begin cruising along furniture, use a developing pincer grasp to pick up small objects, and start social gestures like waving bye-bye. This is a week of faster movement, finer motor control, and growing social awareness.

What's Happening at Week 31

Physical Development

Your baby's crawling has shifted from survival mode to genuine locomotion. Where a few weeks ago they might have managed a few lurching movements before collapsing, many 31-week-olds now cross a room in seconds, change direction mid-crawl, and even speed up when they spot something interesting (or forbidden). According to the American Academy of Pediatrics, babies typically refine their crawling between 7 and 10 months, developing more coordinated cross-pattern movement where opposite hand and knee move together.

For early movers, cruising may be starting. Your baby pulls up on the couch, the coffee table, or your legs, then shuffles sideways while gripping the edge. Not every baby cruises at 31 weeks -- this is the early end of the range -- but if yours does, you will notice them testing weight distribution and balance with every step.

The pincer grasp is also emerging. Instead of raking objects toward themselves with their whole hand, your baby is starting to isolate the thumb and index finger to pick up small items. The CDC developmental milestones notes that this refined grasp typically develops between 7 and 10 months and is a critical fine motor skill that eventually leads to self-feeding, turning pages, and holding a crayon.

Cognitive Development

Your baby understands far more than they can express. They are beginning to follow simple verbal cues -- "Where's the ball?" may prompt them to look toward the right object. They also understand routines deeply now. When you pick up the car keys, they know something is about to change. When you pull out the bib, they anticipate food. This contextual understanding is a sign of rapidly maturing memory and association skills.

Social and Language Development

Waving bye-bye is often the first true social gesture, and many babies start experimenting with it around 31 weeks. At first the wave may be delayed -- they wave after the person has already left -- or directed at no one in particular. This is normal. Your baby is connecting the gesture to the concept, and it takes practice. They are also babbling in longer strings now, sometimes with the rise and fall of real conversation. You might hear "ba-da-ma-ba" delivered with the inflection of someone making a very important point.

Best Activities for Week 31

1. Cruising Course Setup
If your baby is pulling up, arrange stable furniture pieces close enough together that they can shuffle from one to the next. A sturdy ottoman near the couch gives them a short cruising path. Stay close -- they have more ambition than balance at this point.

2. Pincer Grasp Practice
Scatter a few small, safe foods on the high chair tray -- puffs, small pieces of soft fruit, or O-shaped cereal. Let your baby practice picking up each piece individually. This is tedious for them and riveting for you. Every successful grab is a small neurological victory.

3. Wave and Gesture Games
Wave bye-bye to toys, to family members leaving the room, to the dog. Say "bye-bye" clearly each time you wave. Babies learn gestures through repetition and context, so the more consistently you pair the word with the action, the faster it clicks.

4. Crawling Chase
Get on the floor and crawl alongside (or behind) your baby. Many 31-week-olds find being "chased" hilarious, and it encourages them to crawl faster and with more coordination. Laughter during movement is one of the best combinations for development.

5. Container Play
Give your baby a small bucket or cup and a collection of objects that fit inside. Dropping items into containers and dumping them out exercises the pincer grasp, cause-and-effect understanding, and spatial reasoning all at once. In our experience working with families at this stage, container play can hold a baby's attention for surprisingly long stretches.

Creating the Right Environment

A 31-week-old in motion needs a floor that forgives. The faster your baby crawls, the harder the inevitable wipeouts. Cruising attempts end with sit-downs that are really controlled falls. And all of those pincer grasp practice sessions happen best on a surface where dropped food is easy to clean up.

A PocoKoko memory foam play rug provides 1.3 inches of CertiPUR-US certified cushioning that absorbs the impact when your baby's knees hit the floor during speed crawling or when a cruising attempt ends abruptly. The non-slip base stays put even when your baby pushes off furniture, and the machine-washable cover handles the cereal crumbs and fruit smears that come with pincer grasp practice. It is a surface that matches your baby's new pace.

31 week old baby cruising along couch on PocoKoko memory foam play rug in living room

Baby using thumb and finger to pick up cereal on cushioned play mat - 31 week development

When to Talk to Your Pediatrician

Development varies widely at 31 weeks, and not all babies crawl, cruise, or wave at this age. However, the AAP recommends reaching out to your pediatrician if your baby does not bear weight on their legs when held upright, seems to use one side of the body much more than the other, does not sit with support, or has stopped babbling. If your baby is not transferring objects from one hand to the other or does not respond when you call their name, these are also worth discussing at your next visit.

FAQ

What should a 31 week old baby be eating?
At roughly 7.5 months, most babies eat solid foods two to three times daily alongside breast milk or formula. Offer a variety of pureed or soft-mashed fruits, vegetables, proteins, and iron-fortified cereals. This is also a great time to introduce small, soft finger foods for pincer grasp practice. Breast milk or formula remains the primary source of nutrition. Always introduce new foods one at a time and watch for reactions.

How many hours should a 31 week old sleep?
Most babies this age sleep 12-15 hours total in 24 hours, including two naps of about 1-2 hours each and 10-12 hours overnight. Some babies are still waking once at night, which is within the normal range. A consistent bedtime routine -- bath, book, feeding, sleep -- helps signal that nighttime is for longer stretches.

Is it normal for a 31 week old to not crawl yet?
Yes. While many babies crawl between 7 and 10 months, some do not start until closer to 10 months, and others skip traditional crawling entirely in favor of scooting, rolling, or moving straight to pulling up. What matters is that your baby shows interest in moving -- reaching for distant objects, pivoting on their belly, or rocking on hands and knees. If your baby shows no interest in movement at all, mention it to your pediatrician.