How I Wish Baby Could Sit

It is hurtful to hear how 6 month old babies are sitting and my baby who is 8 months and 1 day old cannot sit. He sit for a few seconds, but then will fall over. I don't know what to do anymore. Some people say that he will sit on his own time and all babies are different. The Peaditrician said I need to look at him not as 8 months but more like 6 months, but it still hurts. It makes me feel like I have done something wrong when someone says to me, he is 8 months already and he can't sit. I feel like I am using the premature thing as an excuse as a means to shut the person up and I feel that is wrong. Am I forever going to see him as a premature baby? Am I gonna forever think he can't do something because he was premature? There are babies that are born at full term and they weighed the same as Baby and some babies even weighed less and they were or are at full term, and they are sitting already by 7 and a half month. I know I should be happy with Baby that he is procressing nicely in other areas, like he babbles all the time even in the car. He says mamma, dadda, hoho (no that is not for Xmas, but for hello) and a word which sounds like no, no, no. He can hold his own bottle for quiet a long time which I am suprised at and plenty more, I guess I am just frustrated that he is frustrated because he so desperately wants to sit, but can't. He pushes himself up so nicely, but I think until he can sit he won't be able to sit in that sitting position, but all in time I just have to remember and persevere. Babies are different and I need to let him get there on his own and not try and put him just because I want him to sit.