In general, infants between 6 and 9 months old:
Sit unassisted. While many infants start to work on their sitting skills before this age, their ability to sit well (in other words, without tipping over and hurting themselves) takes some time. By 7 months, the average infant can sit while leaning on both hands for support. By a month later, he will progress to sitting alone without support, and by 9 months, most can reliably sit unassisted for longer periods of time. He can also sit in the basket without a car seat for an extend time! (Read About That Here)
Start to stand. The timing of this milestone tends to vary greatly from one infant to the next. That said, many infants between 6 and 9 months will begin to bear weight on their feet and legs, and by 9 months or so, may even be able to pull to a stand while holding onto furniture. He has started doing this already!!He is standing up on things his bed rails, bar stools & chairs. I never thought we would be baby proofing already!
Consider crawling. The reason we say "consider" is because while infants are generally capable of pulling themselves along with their arms (some even getting up on their hands and knees) by around 9 months of age, the fact is that there are some infants who never crawl. And while the parents of those infants often are greatly concerned, crawling is not truly a milestone, but rather, it is but one way of assessing whether a child's muscle strength and motor development are developing. If you are concerned about your own baby's lack of interest, discuss it with his pediatrician before spending much time worrying about it! Guess what we have a crawler! My child is really crawling!
I don't want to brag, but I have one amazing, determined, advanced little fella ! :)
When did your children start these mile stones?