Honestly!

Me: Boys, did you brush your teeth today?
Boys: Yes.  [playing Xbox]
Me: For sure?
Boys: Yes.  [playing Xbox]
Me: Great!  Just in case, I'm going to go check toothbrushes.

Boys: OK!  [playing Xbox]
Me: If I find out that you didn't, you'll owe me $5.
Jamie: But I only have $1!
Me: I'll take an I.O.U.
Joel: OK.
Boys: Wait!!! [running to beat me to the bathroom to brush teeth]  I think I forgot.