Finding a cabinet position for the thing on his head!
or
Five. One to screw it in and four to tell him how bitchin' he looked doing it.
or
Three skunks fighting over a pickle
First dog: My master calls me Furball. How about you?
Second Dog: My master calls me Sitboy
or
Bike helmets don't fit hippos
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Because there's no one else to wag it for him.
or