TRIGGER: Child on Child I Sexual abuse?

My mother-in-law has lived in Texas for as long as I’ve been with her son, my husband. This year she made the move across country to live back home. She is married and has a 10-year-old step son.She asked me to babysit the 10yo boy throughout the summer. I thought it would be fine. I have two girls age 5 and 2. My 5 year old told me after the first week of watching the 10 year old that he had wanted her to kiss him. I let my MIL know and she brushed it off as kids being kids. After the second week, my 5yo informed me that the 10yo tried to persuade her into taking off her pants. I let my MIL know and told her I would not be watching the 10yo any longer. This past week, the 10yo’s dad messaged me asking if I could keep 10yo for a few hours for date night. I was hesitant but eventually agreed, since it’d be for a few hours. All was fine, until it got quiet. I was with my 2yo and the other 2 were playing barbies (I could hear them up until the point the door was closed and I immediately went to investigate.) The 10yo was sitting behind the door so that it could not be opened all the way. I caught what was the midst of my 5yo sitting in 10yos lap. He immediately started saying how they were just playing Barbies. I told them to go back to the living area so we could watch a movie until his dad came to get him. After trying for 30 minutes to contact his parents, they finally answered. I told them what happened and they came to get him immediately. But that was it, and they left. No explanation or apology.My MIL assured me they had taken care of the situation and that he wouldn’t do it again. But THREE times it has happened. With no serious repercussions or counseling from his parents. I have been sick with worry and guilt since it happened. I don’t want to bring my 5yo into a serious case where she will be questioned because I don’t want her to remember this. I tried casually talking to her about it and she shuts down and cries, telling me she’s scared. I’m very worried about my daughter and the future she has with her grandmother. Any advice in the matter would be appreciated. via /r/Parenting https://ift.tt/33SqSYu