When do babies sit up? It’s a significant milestone in a baby’s life, and there are many steps that they must achieve before this can happen. When babies are born, they have no sense of balance. Balance is one of the last senses to fully develop after vision, hearing, touch, taste, and smell. Balance develops incrementally over the first year as babies begin to get a sense of the gravitational pull on their body and orient themselves to being either horizontal or vertical versus upside down, as most babies spend the last few months in utero.1
A Baby develops from their head down and from their core to their extremities. In other words, a baby develops strength and control in their neck and hold their head up before they have the trunk muscles to roll over, sit up, and eventually pull to stand. They also develop core strength through their abdominal and back muscles before they have the dexterity in their hands to hold and play with toys and use their legs to crawl and walk.
How Does Sitting Up Fit Into This?
Babies must develop balance, core strength, and control to sit unsupported. Let’s break this down because there are a couple of different types of sitting.
Babies can sit in supported sitting as soon as they can hold their heads up. Supported sitting is when the baby leans against something—for example, a parent’s leg, inside a boppy, or a pillow. Babies need to be closely supervised in supported sitting because they have some abdominal strength but can still topple over.
Supported sitting usually starts around three or four months old. It is a significant milestone because it helps to strengthen those little trunk muscles and gives babies a new vantage point from which to see their world. This new stage is excellent for visual development.
From supported sitting, babies can perceive new depths in their visual field. This is convenient because depth perception develops rapidly, right around six months old. This time of supported sitting also helps babies strengthen their neck muscles even more, as they are probably turning left and right to take it all in.
Babies will also sit in a version of supported sitting when they prop themselves up by placing their hands on the floor in front of them at around three or four months old. This is also great for developing strength as weight-bearing through the arms builds strength in the wrists, elbows, and shoulders to prepare for crawling.
Typically around five to six months old, babies will get better at unsupported sitting. It is always important to closely supervise babies while sitting until they are very adept at functional sitting.
Functional sitting is when babies can get in and out of sitting themselves. Babies may crawl, sit and play with a toy for a minute, then crawl some more. Babies may also lie on their back, then roll to their side, then push up into the sitting position, then transfer back to a roll all by themselves. This is functional sitting; babies usually get good at this between six and ten months old but may still need practice.
Functional sitting is the goal, and babies should spend as much time as possible on the floor during these months. This allows them to learn functional sitting through trial and error and general strengthening. The more they practice, the stronger they become and the better their balance is.
Parents often think baby chairs and Bumbo seats help babies learn to sit. However, these devices restrict free movement. They do not allow babies to build the necessary core strength to sit unsupported and graduate to functional sitting.
How to Help Babies Learn to Sit
We have a few tips to help build strong little sitters.
- Start holding your baby upright as soon as they are born so they feel what it is like to be vertical and begin to develop a sense of balance and position in space.
- We love vertical baby carriers for babywearing.
- Allow babies lots of tummy time starting at birth. This will help develop neck and core strength that will aid in sitting.
- Prop baby against a parent or caregiver’s leg to build comfort in the sitting position.
- When babies are in supported sitting, hold toys at their eye vision and encourage them to reach for the toy to challenge their balance slightly and get them to interact. Also, play patty cake in supported sitting to help build balance.
- Use a large beach ball or physioball to help build sitting skills. Sit baby on the ball and use your body to support the baby’s body as you hold them at their hips and roll them slowly side to side and forward and back. This challenges balance and builds core muscle groups as babies work against gravity to maintain their upright posture.
- Allow babies as much floor time as possible to encourage functional sitting. When babies are sitting, place toys just out of reach so they have to move to get the toy.
- When baby is rolling or scooting around on their belly, hold a toy up so they have to sit up to reach it, then allow them to play with the toy while sitting.
Sitting unsupported is an exciting milestone because it allows for so much independence. Babies will love it, too, because it gives them control over much more of their little world.