Perhaps it was a fig he saw fall from the tree

Overheard at my table, while I was chaperoning my daughter's fifth-grade class on a field trip to Starbase Connecticut :

Instructor: Turn to the page about Isaac Newton.

GG (to the students at my table): Isaac Newton, this guy's really cool.

Student 1: Was he the guy that invented the cookie?

Student 2: The Newton?

Student 1: Yeah, the Newton cookie.

GG: The Fig Newton? No, I think that was someone else.

Student 3 (without a hint of irony): It was probably his brother.