My family are nearly all dead, and lived before anyone would have got a diagnosis. I never knew my grandparents, or anyone else of their generation, but I had one uncle who I'm sure must have had it. Apart from that, I can see some characteristics that I have in my late father, and one much older brother, but I doubt it would be anywhere near enough to get a diagnosis, or even be recognised by anyone else. I think I see it only because I have been diagnosed and think it must be unusual for an NT. My other much older brother, who I have no doubt is NT, has often commented on there being something odd about the family. I suspect that there has been mild autism in my father's side of the family, but not enough for it to be recognised. Maybe it's also a cultural and generation thing, where the time and way they lived didn't make it obvious, or cause much of a problem, but modern life makes it harder to cope with.