does he have toys to play with on the floor? dd has an electronic ball that's much easier to watch sitting up. can he sit in high chairs or a boppy to work those muscles? and also, more time spent on the floor.
I've tried the boppy no luck. He does sit in his highchair 3 times a day. He's on the floor a decent amount - maybe I need to put him on the floor more. I'm a little frustrated - I feel like he's not going to be able to play with his Christmas toys.
DD just started, but she still needs some assistance, like the boppy or me behind her. I honestly think she just likes to lay around. She would fuss and arch her back until you laid her back down. Now she see's that she can play with things better and is doing it a lot more often.
My DS won't sit up unassisted yet either, I usually put him in his bumbo seat a couple times a day, and highchair, he plays in his jumperoo etc. I'll let him sit holding my hands but as soon as I try to let go, he automatically starts to head for the floor. Some babies just do things a bit later, just work with him when you can, and try not to worry too much about it, babies like to set their own pace.
Re: 8 months not sitting up unassisted...