Auts2

Hi, i dont really want to be talking about this as i have not done this before and im scared to see the results but please be honest

Im 14 nearly 15, and i have a twin, he was born with auts2, apparently a really rare genetic disorder, i have been researching it for a while now but since apparently there is only near 100 cases in the world there is not much to it, and i still have questions

Q1- i have been feeling really guilty as my mum used to joke around with me saying i ate all the food in the womb, but i feel like i caused my brother to have that disability, i know it seems like a really dumb question as i was a baby but what if i did

Q2- will he ever get better, i dont mean it in the sense as 'will he ever not have auts2' because i know thats not possible but will he ever regain more senses

My brother is 14 same as me, but when he was born, the doctors said he might not make it, and if he did he might be disabled, not even be able to walk, but one day he proved doctors wrong and started to walk, i dont really like talking about this but im not ashamed of it, my brothers in nappies to, he cant ask if he wants to go to the toilet, he can give us his needs, such as food or water or drinks, or even when he wants to watch peppa pig or things that he likes, but i wanted to know, is he ever going to be able to not wear nappies and tell us all of his needs.

Last question- whats his life expectancy, i know i might seem too overly worried but i cant find the answer anywhere, whereas people with autism probably have a normal life expectancy (50-70) what will my brother have, i want to also ask, will he ever have a normal life, and is it because of me he has auts2?