Is age difference weird if you've dated others as young as those whose parents are not much older than you?

Like when people say they're married to spouses 13 years younger, but then there are people whose parents are only 20 years older than themselves. Maybe even weirder if the age difference between their parents and their grandparents are almost the same. I mean, imagine one family parenting at around 30 years old, and a family parenting at around 20 years old. When her grandpa is about as old as his dad.

Or am I just overthinking here?