US Presidents

Me: Test me, I've been studying the US presidents.
VI:  how come?
Me:  for my students.  Go, just the first seven though.
VI:  I know who the 51st is.
Me:  Really?  I don't think anyone knows that yet.  lol

The next day (relaying the above convo to mom with VI in the car)
Mom:  Aren't we are on the 52nd?
VI:  lol!
Me: who are you people?

Me:  Tell me who the 16th president is.
VI:  Roosevelt?
Me: Abe Lincoln
Mom:  I could have told you that.  You spoke too fast.
Me:  Really?
Mom:  Of course, we had to study for this in the US.
Me:  my bad