You're not an old man!

A few nights ago, Daddy groaned as he was bending down to bathe the zoo inmates.

Devlin: What's wrong Daddy?
Daddy: Nothing. it's just that Daddy is getting old and his bones hurt. I'm an old man.
Devlin: You're not old. Old people have lots of white hair. You don't have lots. So you're not old.
Daddy (laughing): Thank you Devlin. Is Mommy old then?
Devlin: No.
Daddy: What about Auntie Grace?
Devlin: No - she has no white hair. She's young.
Daddy: How about Grandma?
Devlin: No - she has black hair. She's not old.
Daddy: Well, what about Grandpa?
Devlin: Ummm, he has a bit of white hair, but he also has black hair. He's only a little bit old.