Hello,
Interesting you should ask, as I've been thinking about this quite a bit. I believe myself to be NT and have an older sister (by less than 2 years) who I suspect is somewhere in the range of AS, probably subclinical. Now that my son has AS, it's all starting to come together. I clearly remember the obsessions, the rigidity of thought, the awkward social interactions. Whenever I share a story about my son with my Mom, especially a perplexing one, she tells me it reminds her of when my sister did something as a child.
For me, having this context makes the whole thing a whole lot easier to understand and accept. We've never been especially close, and now I understand that it's not just that our personalities are very different. OK, I'm still working on the acceptance part .