Dreaming Big

Walking home from school today, Pie announced apropos of nothing, "When I grow up, I'm going to be a doctor!"

Me: What kind of doctor?
Pie: A marathon doctor! A racer doctor!
Doodles: There's no such thing!
Pie: No?
Doodles: There are four kinds of doctor. There's no marathon doctor.
Me: What are the four kinds?
Doodles: There are ambulance doctors, hospital doctors, office doctors, and come home doctors.
Me: What's a come home doctor?
Doodles: That's the kind of doctor who comes to your home.
Me: Oh.
Pie: I'm going to be an office doctor. A racing marathon office doctor.