Infant Development Guide (6–9 Months): Sitting, Crawling & Early Mobility
Your 6–9 Month Baby’s Development: Sitting, Crawling, and Exploring the World
Between 6 and 9 months, babies often discover the joy of independence. This stage is full of motion — rocking on hands and knees, sitting, tall kneeling, clapping with excitement, and finally crawling toward something they love. It’s a season of playful exploration and growing confidence, where baby mobility and gross motor skills development happen naturally through curiosity, movement, and joy.
Be Proud Of…
Your baby’s determination to balance and explore.
The way they pivot, rock, and problem-solve their movements.
How you’ve supported safe exploration at home.
Look Forward To…
Sitting independently and clapping with joy.
Crawling to reach a favorite toy.
Waving, babbling, and responding to their name.
Let's focus on Sitting with Confidence: Independent sitting, balance practice, getting to sitting independently
Independent sitting is built through practice, play, and exploration. Here are simple ways to support your baby as they develop balance and learn to move in and out of sitting:
Getting into sitting: Instead of placing your baby straight into a sitting position, give them opportunities to discover it on their own. From sidelying, gently help them tip up and push through the arm on the floor. This builds the strength and coordination needed for true independent sitting.
Balance in sitting: Place toys just within reach but slightly to the side so your baby practices leaning, shifting weight, and correcting posture. These little adjustments teach them how to tip and return to sitting with control.
Reaching in all directions: Encourage reaching forward, sideways, and even twisting behind for toys. Every reach strengthens the core and prepares them for real-life balance challenges.
Protective reactions: Gently tip your baby side-to-side while they sit so they practice catching themselves with their hands. These protective reactions first develop to the side, then forward, and later behind them.
Core strengthening game: Try “around the world.” Sit your baby on the couch facing you with their hips and legs supported, then guide their body in small circles — side-to-side, forward, and backward. This playful game activates their core in all directions and builds the stability they’ll use for sitting and beyond.
Parent Question: Should my 7-month-old sit on their own?
Short answer: No. Sitting on their own is just one piece of development, and there’s a wide range of normal. What matters most is whether your baby is practicing the building blocks for sitting, like:
Rolling and pivoting on the floor.
Pushing up on their hands.
Reaching and playing in tummy time.
Beginning to balance with support in sitting.
All of these pieces come together to make independent sitting possible. If you’re seeing steady progress with these foundations, your baby is most likely on the right track.
Additional parent question: What if W-sitting?
W-sitting (legs out to the side in a “W” shape) isn’t always a problem — but if it’s your baby’s go-to position, it’s worth noticing.
It may mean your baby is avoiding using their core and trunk muscles. Over time, this can affect balance, coordination, hip development, and how they move through other milestones.
Try this instead:
Use toy placement to encourage other positions — to the side for side sitting or up high for tall kneeling.
Encourage play that builds core strength — crawling, reaching, climbing.
Use small chairs or low stools for seated play with feet on the floor.
Occasional w-sitting is totally fine. We just don’t want it to be the only way your baby sits. If it is, a pediatric PT can help guide next steps.
Let's focus on Crawling Prep: Hands + knees rocking, “planking”, prone pivoting
Before babies crawl, they practice smaller movements that build the strength, coordination, and confidence to get there. Important precursors include tummy time, rolling, and dynamic sitting play. Crawling often develops alongside pulling to stand and cruising. Along the way, upper extremity weight bearing also strengthens the hands and begins to build the arches of the hands needed for future fine motor skills like writing and grasping.
Here are three powerful pre-crawling skills you can encourage at home:
Pivoting in prone (on the belly)
How to do it: Encourage your baby to roll onto their tummy. Place toys in a circle around them. Encourage them to reach, move, and pivot toward the toy. You may see them pivot in half-circles or around their belly button. Ensure they go both ways!
Why it matters: This movement activates the oblique muscles and builds diagonal patterns through the body. It helps babies learn purposeful movement across space — a big step toward crawling.
Planking and “downward dog”
How to do it: When your baby pushes up on straight arms (plank) or lifts their hips high with hands and feet on the ground (like a downward dog), cheer them on and let them hold as long as they’re comfortable. Place a toy just in front to keep them engaged.
Why it matters: These are full-body strengthening moves that build extension through the arms, core, and legs. They’re strong pre-crawling indicators for some babies — but not every baby will do them, and that’s okay.
Rocking on hands and knees
How to do it: Once your baby gets onto hands and knees, place a toy just out of reach to encourage rocking forward and backward. You can also gently guide their hips to help them feel the movement.
Why it matters: Rocking teaches dynamic weight shifting and motor planning. These small, repetitive movements lay the foundation for coordinated four-point crawling.
Baby on their tummy pivoting toward toys, building core strength and diagonal movement patterns for crawling.
Parent Question: What if my baby scoots instead of crawls? Does crawling matter?
Hands-and-knees crawling is the most energy-efficient way for babies to move across the floor — but not all babies choose that path.
Some experiment with patterns like the inchworm crawl, butt scooting, or hitch crawling.
Inchworm crawling has a limited back-and-forth pattern and may point to challenges with strength or motor planning.
Butt scooting limits how much a baby crosses midline and reduces the sensory input and weight bearing they get through their arms, knees, and legs — all important for building strength and coordination.
Hitch crawling (using one leg bent forward while dragging the other) also avoids crossing midline and shows that weight isn’t being shared equally on all fours.
Butt scooting isn’t automatically a problem — it’s a clue. As a pediatric physical therapist, I don’t just note what your baby is doing, I look for why their body is choosing that movement. Many butt scooters have underlying asymmetries or “blocked” movement patterns. For example, they may rotate their chest more easily one way than the other, or sit with more weight on one hip, leaving the opposite side shortened. On their tummy, those same imbalances can cause one leg to drag while the other does all the work. Crawling forward simply isn’t available — so scooting becomes their go-to strategy.
So why do we care about crawling? Because it’s about much more than moving forward. Crawling is a whole-body and brain workout that builds:
Core strength and shoulder stability.
Connections between both sides of the brain (crossing midline).
Eye tracking and depth perception.
Spatial awareness and coordination.
Foundations for later skills like writing, using buttons and zippers, and climbing monkey bars.
Good news: Even if your baby skips crawling at first, practicing crawling later can still bring these benefits at any age.
Bottom line: Alternative movement patterns like scooting or hitch crawling aren’t always a concern, but they are worth a closer look. By uncovering the why behind the movement, we can help your baby unlock their full range of motion and support healthy, balanced development.
Baby rocking on hands and knees, practicing weight shifts and motor planning to prepare for crawling.
Parent Question: What if my baby scoots instead of crawls? Does crawling matter?
The best way to encourage mobility is to give your baby a safe space to move and explore. Choose a designated area in your home — a soft mat with a few toys works great — and let your baby take the lead. Here are some simple ways to support gross motor skills through play:
Independent sitting play: Let your baby sit with toys just out of reach. This encourages them to lean, reach, and even begin transitioning into hands-and-knees.
Tummy time with a goal: Place a favorite toy just beyond reach on their belly. As they move toward it, they practice the early skills for crawling. Start close, then move the toy farther as they get stronger.
Encourage transitions to standing: Put toys on a low surface (like a couch cushion or play table) so your baby practices moving from sitting to standing.
Play in tall kneeling: Encourage your baby to kneel at a couch or low surface, bearing weight through both legs while reaching for a toy on top of a cushion. This position strengthens the glutes and core — important muscles for cruising and walking.
Interactive games: Peekaboo, waving, clapping, and other playful back-and-forth games don’t just make movement fun — they also support early language and social development.
Remember, mobility develops through exploration and repetition. By creating safe opportunities for your baby to move in different ways, you’re giving them the foundation for confidence, coordination, and independence.
Dr. Nicole’s Top Tip: “Movement is a child’s first language. Let your baby explore with joy and curiosity.”
Common Parent Concerns About 6–9 Month Development
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Short answer: No. Sitting on their own is just one piece of development, and there’s a wide range of normal.
What matters most is whether your baby is practicing the building blocks for sitting, like:
Rolling and pivoting on the floor
Pushing up on their hands
Reaching and playing in tummy time
Beginning to balance with support in sitting
All of these pieces come together to make independent sitting possible. If you’re seeing steady progress with these foundations, your baby is on the right track.
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Butt scooting isn’t automatically a problem, but it is a clue. It tells me, as a pediatric physical therapist, to investigate why your baby’s body prefers scooting. Frequently, it points to asymmetries or blocked patterns that are worth treating so your child can unlock new movement options — including crawling.
And here’s the exciting part: when we address these asymmetries, it’s amazing how many children spontaneously begin crawling!
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W-sitting (legs out to the side in a “W” shape) isn’t always a problem, but if it’s your baby’s go-to position, it’s worth paying attention.
It can be a sign that your baby is avoiding using core and trunk muscles. Over time, this may affect balance, hip development, coordination, and how they move through other milestones.
What to try instead:
Gently help them sit criss-cross, side sitting, or legs forward
Use play that builds core strength (like crawling, reaching, or climbing)
Try small chairs or low stools for seated play
Occasional W-sitting is okay — we just don’t want it to be the only way your baby sits. If it is, a pediatric PT can help guide next steps.
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If your baby avoids tummy time and only wants to sit, they’re probably telling us something. Babies communicate through movement and preferences, and avoidance can be a sign of tension, discomfort, or difficulty managing the position. It’s important to ask why tummy time feels hard for them.
While sitting is exciting, it’s only one part of the big picture. The long-term goal is for your baby to be able to transition in and out of sitting on their own and then return to play on their tummy. Tummy time builds the neck, shoulder, back, and core strength needed for rolling, crawling, and later motor milestones—skills sitting alone won’t provide.
If your baby consistently resists tummy time, a pediatric therapist can help uncover the reason and provide gentle strategies to make it more comfortable and engaging. -
Crawling is so much more than a way to move forward. It’s a whole-body and brain workout that helps build:
Core strength and shoulder stability
Connection between both sides of the brain (crossing midline)
Eye tracking and depth perception
Spatial awareness and coordination
Foundations for later skills like writing, using buttons and zippers, and even climbing monkey bars
The good news: even if your baby skips crawling early on, practicing crawling later can still bring these benefits at any age.
