Baby Development.

Hi, I have a 8 month old baby boy. He's quit healthy but when it comes to development I'm getting a bit worried. I have a friend where our babies are 1 day apart and we were due the same day, so when we compare out babies it makes me worried, my baby boy only sits up on his own, holds toy, holds his bottle when he wants to, says mama, he rolled over only for 1 week and stopped, he hates being on the floor on his belly or back he wont even try putting his legs up under his butt. But my friends baby she's rolling over like crazy she can roll down the hall and back in the matter of 2 mins, she can hold her bottle, say more words, almost crawling, hold toy, etc.
Should I be worried about my baby's development?

All babies are different!
I crawled at 10 months. walked at 12.
My 7 month old daughter is crawling everywhere, standing, walking the funiture, climbing.
i didnt do any of that at 7 months.

Also, my friend had her daughter at 37 weeks and she was 4 pounds. She was army crawling at 6 months but couldnt sit up til 7 months.

My other friend has an 8 month old son and only sits up and says dada.

Dont worry to much   Maybe work on him rolling over a bit more before the crawling. Might be easier

i wouldn't worry, every baby is different.

i wouldnt worry all babies are different. My son is 5 months old and is almost crawling already but thats because he loves being on the floor on his tummy and hes always wanted to go since the day he was born but my older son didnt start crawling till he was 7 months old