The Boy: There have been 502 leap years.
Me: Provided there have always been leap years.
The Boy: What do you mean?
The Husband: There have been more than 2008 years since time began. You mean since the first century.
The Boy: What?
The Husband: Since the first century.
The Boy: Well - OK. There have been 502 4-year periods.
The Girl: What's BC?
Me: That depends...either Before Christ or Before Common Era; same thing.
The Girl: And AD means After Dinosaurs.
Me: Yes - that' s EXACTLY what it means!