My father is the coach of a girls team. I searched through his laptop a while ago. There was a hidden folder with some pictures. They were taken in the locker room with two girls in their shorts showing off their butts. They lean forward with their hands on their knees, smiling to the camera. There were a total of 10-12 of these pictures, where they stand in different positions and with their head between their legs. On the last pictures they have pulled down their shorts and show off their bare buttocks. Their intimate parts are clearly visible, both the vagina and the butthole. In the last picture their shorts are completely gone, and they have their tounges out and laugh together while showing off completely undressed.. One thing is what he has photographed, but I wonder if he actually has had sex with them? If so, he has cheated on my mother. I also wonder if it is illegal that he has taken those pictures and I guess it would be illegal anyway if he is screwing them. Embarrassingly enough, I was turned on by these pics, so I have copied them and mastrubated. It is probably illegal also. The girls are 18-19 years old and very pretty. What should be my approach to this? Tell someone or just leave it?