Yes. I think most of us who have children on the spectrum start to wonder if other family members have autism. We may even question it about ourselves (I certainly have). It's hard to know if our relatives genuinely are on the spectrum or if we've just lost all objectivity. When my son first got diagnosed, I started to think all little kids around me had autism!
I do, though, think my mother exists somewhere on the spectrum and would probably be diagnosed if she were a child today. Even though we were first-time parents, both my husband and I started to see signs early on with my son: flat affect, no eye contact, delayed speech, floppy body, low muscle tone, poor coordination, and so on. My mother, on the other hand, though there was absolutely nothing wrong with him. I thought that strange since she had reared four of us but seemed to know nothing about normal child development and meeting developmental milestones. I think my son was a lot like she had been as a kid, so she didn't perceive anything as being amiss.
It's ironic that my mother's lack of empathy regarding my son was what got me reading about emotionally absence mothers. I hope you have found some blessings in your son's diagnosis as I have with mine. I love my boy, and I can't imagine who I'd be now without having gone on this journey with him. I hope you and your son are doing well and you have some loving and supportive people in your lives.