[genedad]

Dawn's brother, Danny, graduated high school and wanted to enlist. He signed all the papers and was going in after the summer. He and his mother had moved and he wanted to spend his summer at the lake. We only had a one bedroom apartment but we had the sleeper sofa so we told him it was fine to stay with us.

The first weekend that he is with us, we all go waterskiing with Uncle Bob. As always we were drinking and having a good time and at one point we cruised to the sandbar and anchored. Some other friends had anchored there as well so we ended with abou three boats tied off together. Dawn is being herself and very flirty. A couple of guys ask her to flash her tits to them and she does. They ask her to show her ass and she bends over, pulls her suit to the side and shows it. After a while the four of us are relaxing. Danny and I are sitting at the back of the boat. Uncle Bob is in the driver's seat and Dawn is leaning against him with her back against his chest. As we watched, Uncle Bob casually moves the bottom of Dawn's suit to the side and starts playing with her pussy. He is rubbing her clit and slowly rubs a finger through her slit. Dawn smiles as he is doing this.

"That's so nice. I love having my pussy played with. Please keep it going. Put your finger inside." Our uncle starts drilling her c*nt with his finger. Meanwhile she reaches behind her and feels his cock through his suit. "Oh you're happy to see me. You like to play with your niece's pussy don't you."

I did not want to deal with a sex party at the sandbar. Unlike the poker game day, the weather was beautiful and there were a lot of boats there including families with children. I stopped them and suggested that we move off. We untied from the others, pulled up our anchor and Bob moved slowly away. Dawn never moved from his side. As he was driving she stood by his side. Danny and I were treated to our uncle's hand under Dawn's bathing suit holding her bare ass. It looked as though his fingers were either in her ass or pussy.

"You're okay with this? You don't mind that Uncle Bobby is playing with my sister?"

"Danny, I let her give you a blow job remember? Of course he did. That was probably the best day of his life. "Uncle Bob takes us waterskiing all the time using his boat and his gas. He buys the drinks and we have a great time together. Your sister loves sex and I like to watch her do different things. This works for us."

We were now out in the middle of the lake and we stopped the boat. It was broad daylight with a good amount of traffic. I offered Uncle Bob one of Dawn's blow jobs. We really couldn't do much else as there was too many people on the lake. He agreed and I told Dawn to get on her knees. She opened his suit and lowered her head onto her uncle's cock. Danny and I watched her head bob up and down and kept our eyes out looking for the marine police.

"God that is so hot. I never saw anyone give a blow job live. I've seen porn but this is way better. I can't believe that I'm watching my sister. Are you sure that you're okay with this? After all she is your girlfriend."

I again assured him that I was fine with it. "I'm in control. I tell her who to have sex with and what sex act to perform. Your sister is very highly sexed and we prefer this to her going behind my back and cheating on me."

Dawn is still fellating her uncle. She has one hand jerking his shaft in her mouth. Her other hand has pulled her suit to one side and she is rubbing herself off. I can tell that they are getting close. Uncle Bob puts his hand on the back of Dawn's head and rises up, pushing his cock in her mouth. He climaxes in Dawn's mouth. It is to much and we see his cum running out of her mouth. Dawn swallows what is in her mouth and releases his cock. She is still rubbing her clit.

"That was so good. I love the taste of come. Oh look I missed some." She licked up all of the come that was left on Bob's shaft at the same time pulling on her clit until she also orgasmed. Dawn was a squirter and released fluid every time she orgasmed. She pulled her suit back over her crotch covering her pussy. Her suit soaked up the liquid and now we could see a big wet spot.

"That was great but we have to get back. I promised your aunt that I would take her to dinner." Uncle Bob gave the boat some gas and we headed in. Dawn came to sit with Danny and me.

"Did you enjoy that little brother? Did you like watching your sister?" Danny shook his head. "Well, if you stay with us this summer, you will probably see more. You okay with that? Maybe more than just watch." Dawn laughed. Danny's face got really red but looking at his bathing suit you could tell he liked the idea.

I'll fill you in later on what happened when we got home.