Grandboy (stands up, cracks his head): OWWWW

Me: O hey that looked like it hurt.

Grandboy: WHY DO THEY MAKE THESE BEDS SO SHORT?!?

Me: Because they are bonk beds.

Grandboy (does THE LOOK)

Me (does the INNOCENT look) 

Grandboy: Oh I get it because they are bunk beds you call them bonk beds. Gwumpa, sometimes…