My mom had her first child when she was 19, a lot in between, me (and a twin) when she was 37, a younger brother the next year, and my youngest brother at 41 (and there was supposed to be another the next year, but the doctor convinced her to get her tubes tied).
My dad is 17 years older than my mom.
People apparently thought that my mom was covering for my oldest sister (who was 18 at the time. She had her first at 19) when she had me (plus twin); that our sister must have gotten pregnant and didn't want people to know. lol
To be fair, there were a few "gap years" between the oldest bunch of my siblings and my birth.
That's not so bad though. When I was older, my middle sister was CONSTANTLY getting mistaken for my mom and she's only 8 years older than me!
Everyone also constantly thinks she's the oldest girl, even though there's a 10 year age gap there.
Poor her, I do think that bothers her a bit. Though she jokes she never had trouble getting into bars.
My brother's (now ex) wife was negative about having children "too old". I can't remember exactly when that was, but I think it was 30 (I used to have a "plan" as a child - that I wouldn't have kids till after college and a few years on the job - which worked out to after 30, so I'm fairly sure that was her 'stopping' age).
It was kinda funny at the time, because her hypothetical situation didn't really apply to me, because she was older than my brother (her hypothetical situation for some reason focused on my dad), and because no one had a high opinion of her parenting skills anyways - and funnier now because her latest kid was born when she was 35.