We still don't know what my brother has, besides some kind of autism spectrum disorder. I'm twenty-two, not thinking about having kids any time soon, but it still worries me to know that I could be carrying an unknown genetic mutation that had such a severe effect on my brother. When I brought it up to my older sister, she didn't seem concerned. I know that she didn't have as difficult a time growing up with him as I did, so that may explain some of her lack of concern. My brother is a delightful person in a lot of ways, and I am glad that my parents didn't put him in an institution. But I don't think I could raise a child with the same problems that he has. My brother is enough, and my childhood with him is enough.
Maybe I'm incorrect that his condition is due to a genetic mutation. There isn't a history in my family as far as I know, besides one maybe mildly retarded great-aunt. But it seems so similar to Fragile X. So, my family isn't directly affected by Fragile X, but this is the closest that I know to whatever my brother has. I'm not asking for anything really, but you all are probably the ones who most understand my situation, and there is some comfort in that.