Two dogs

This reminds me of a joke:

Three Native American boys were sat around their camp fire. That's camp as in boy scout, not as in gay.

One of them pipes up, "How come I'm called Tall Tree?"

"That's easy," replies Howling Wolf. "When I was born, the first thing my Mother saw was a howling wolf, so she called me Howling Wolf. When you were born, the first thing your Mother saw was a tall tree, so she called you Tall Tree."

"Ok,' says the third. "So how come I'm called Two Dogs Fucking?"