My brother & I have actually shared a few girls, so yeah, I've seen his cock. He's 2 years older than me & we use to walk around naked alot. That stopped when we got to be a little older. Then one day, when I was 16, I went to his room to ask him something. When I went in I saw his girlfriend giving him head. Thankfully they didn't see me. She was giving one hell of a blowjob & I went back to my room & jerked off. The first time we shared a girl, it was actually her. On my 18th birthday she said we should celebrate by having a threesome. She said she loved his cock (he's about 8x6) and she had always wondered if I had a big one too. It took some convincing, but she talked us into it. We had a great time & it was one of the best gifts i've ever gotten...lol nd no, we've never & never will do anything with each other.