My mum wasn't exactly young when I was born as she was 33. 10 years later, she had my sister when she was 43. My sister always regrets that my parents were older than the average, and they often got mistaken for her grandparents.
33 is not young...
My dad was 51 when I was born and 54 when my sister came along, lived until he was 79 so we had him around well into our adulthood. I have to say nobody ever mistook him for our grandfather, no kids ever teased us about having an 'old' dad...I fail to see how anyone can regret their parent's age when it is something you grow up with and see as normal from the beginning. My husband is 52 and our kids are aged 6 and ten, nothing is ever said to them about that and they'd say so if there was. So many grandparents collect their grandchildren from school and care for them these days that they don't stand out as looking out of the norm among the mums and dads. I cannot see where kids notice 'age' as such in adults...unless dad looks like Steptoe