I have 10.5 month old boy/girl twins. My son is right on target as far as crawling, pulling up and getting himself into a sitting position. My daughter just started crawling a few weeks ago but on her belly. She can get up on all fours but doesn’t crawl this way. She has not figured out how to sit herself up from her belly and if I stand her next to a piece of furniture she can support her weight on her legs and stand for quite a while playing with a toy but she just throws herself backwards when she has done, there is no getting herself down easy. I am concerned about her being delayed and was wondering what I can do to help her.
I am wondering if your twins were premature or on time? If they were premature, than giving them each some extra weeks (especially your daughter) to complete developmental milestones would be expected to adjust for how early they were born. Your daughter sounds like she has some nice skills in place and is just perhaps having trouble coordinating her movements to transition in/out of sitting, to crawl on all fours and to get down from a standing position. She may also need to increase trunk strength to complete some more complex motor movements. I am happy to hear she can belly crawl, can assume hand/knee position, as well as stand and bear weight while playing.
The best way to help her transition up and down into sitting (I am assuming she can sit independently with hands free for play when you place her into a sitting position?) is to help her rotate her body. Instead of picking her straight up from her back or belly when in the crib, on the floor or changing table, instead try rotating her to her left side, place your left hand under her left shoulder and your right hand on her right hip and gently rotate her up into sitting letting her do the majority of the work and hopefully she will place her left hand on the floor to help push. Do the same thing by rotating her to her right side and switching hands, one under her shoulder, one on her hip. Think of how you sit up…you don’t simply sit straight up from lying on your back, you rotate to either side and rotate up into sitting and this is what she should be doing. Try doing this after every diaper change. You can guide her down from sitting in the same way…rotate her trunk to the side and encourage her to place both hands on the floor as you rotate her into a hand/knee position. Place toys to her left and right sides just out of her reach to encourage trunk rotation and encourage her to rotate naturally down to hand/knee or belly. You can place her in hand/knee over your own leg or over a roll (tape some large soup cans together and cover with a towel to make a roll to place under her belly)…gently rock her back and forth in this position and place toys to left and right sides just out of her reach to encourage her to shift her weight and reach for things. This will encourage her to bear weight on one hand and then the other as well, which she will need to do for crawling.
You can use a large playground or exercise ball for fun and bounce her on the ball in a sitting position, slightly tipping her side to side and then back to front to increase her tummy strength. Babies usually find this fun and you can sing songs to keep them entertained. Using a small ball or the roll I mentioned before you can place her on her tummy and roll her forward encouraging her to place both hands on the floor and bear weight, then come back to knees and bear weight. Sing songs such as Row, Row, Row Your Boat.
To work on pulling to stand and returning to sit you ideally want your daughter to come from a hand/knee position into a 1/2 kneel position, then up to stand. You can sit by a low table or cardboard box turned upside-down that is about armpit high for your daughter when she stands beside it. Place your daughter in a kneeling position (both feet under her bottom, make sure her bottom doesn’t drop in between her feet), help her bring one foot out into a half kneel and then boost her up into standing. You can also sit her on your lap, so both of her feet touch the ground and encourage her to pull up from there, sort of like doing squats and encourage her to bend her knees and lower into sitting on your lap again. Many babies simply fall backwards or just plop onto their bottoms when first pulling to stand, so she’ll need practice time to bend her knees and lower to sitting.
If you continue to have concerns and she is not hand-knee crawling, or getting in or out of sitting by 12 months you may want to contact your local early intervention provider to have a physical therapy evaluation to get other suggestions or see if she qualifies for services to help her catch up on motor skills if she is still behind. I am sure it’s hard not to compare your twins, but since all children do things at different rates and boys sometimes tend to be more motor oriented than girls, it’s not that unusual that your children are completing motor milestones at different times.