How do you know a 4 year old lives in your house? The word “butt” becomes the funniest word in the world. Anything with “butt” affixed to it is instant comedy gold.
Pickle + Butt = PickleButt
Donut + Butt = DonutButt
Bunny + Butt = BunnyButt
Say loudly and fall over in a pile of giggles. Continue ad infinitum.