Hi slivia! my son was very behind in development when he was 9 months old. He wasn't crawling, pulling himself up to stand, cruising or anything. I would put toys in front of him just to try and get him to crawl. His pediatrician refered us to a free program where people come out to your house to assast and help with thier development. When they came, they did a 2 hour assestment and said he was WAY behind. Being a first time mom, I was very upset! They wanted to schedule him for therapy 4 times a week and all this othet stuff. My hubby and I agreed to wait it out a little longer and just work with him at home. Sure enough, he caught up. now @ 12 month old, he can't be stopped! he walks, runs, climbs, dances, claps, sings and all sorts of things. The point: all children are different. Just because a text book says he should sit up at 6 months, dosen't mean he's ready to. If he has a clean bill of health from the doctor, then just continue working with him. don't worry, when he's ready to show you all his tricks and talents...he will! He just likes laying down, there's nothing wrong with that.