fun with math

Every night we watch the show Arthur just before bed. Tonight's episode was about geniuses. Towards the end of the show Scott started in with...

dad: gage, do you know any geniuses?

gage: yes, (name withheld because that's not really the point but he's a classmate)

mom: gage, he's SEVEN...he's a year and a half older than you

gage: I know....(brief pause)...but when he's nine I'll be SEVEN.

Who's the genius now?