[lavatea]

My daughter starting sitting up during her fifth month. Aiden is now six months old (although you can adjust his age for being a preemie and consider him five months old) and is showing no signs of being able to do this. I know it's too early to start worrying and you shouldn't compare your children, but I am wondering what the "normal" age range is for babies to start sitting unassisted? Also, do things like sitting, crawling, and walking have more to do with their age or with their physical size? Because he was so small at birth, Aiden is about the size my daughter was as a two month old, although because of his age he's definitely more mature acting.