I see them and my 3-legged dog go at it at times. My neighbor also has goats. Went to a birthday party there. One younger person, shall remain nameless, consumed a few beers and decided to play male ram with a motorcycle helmet. Were is a video camera when you need one. Thought he was going to get a compression fracture but it was funny to watch.
They have never headbutt me but they do make "gestures" with kids so I have to be careful with my kids.
My "dog house" would be my oldest son's tree fort.