What is this world coming to?!

This morning I sat with my children in my car waiting on the bus because it was too cold for them to stand in the wind. When the bus arrived I kissed them and sent them to the bus. While I waited for the children to load I noticed that the bus driver was not letting anyone on and was talking and waving around a piece of paper. I turned my radio down and my heat off, rolling my window down I tried to hear what she was saying to the children. Afterwards she spoke with several mothers lingering in the line with their children. Once all the kids were on and the parents began walking away I asked one mother I knew what was going on. She replied, "2 boys were caught performing oral sex on each other yesterday afternoon on the bus." I wanted to scream. WHAT! I was horrified to think that my kids may have witnessed this and didn't tell me. My kids, 10 and 5 know about sex. My 5 year old doesn't know the ins and outs but she has the jist that it is something special and something adults do. To think that she could have seen these two boys doing this makes me crazy. I experienced some abuse as a child and I vowed to prepare my children enough and to keep the lines of communication open so that they can protect themselves, because like it or not parents when they are outside your line of sight shit happens and you can't protect them forever against every threat. This is a case in point. I guess what scares me the most is that these two boys were 6 and 9. So close to my kids ages, not friends of theirs because I'd never heard their names before, but still its scary that predators you have to worry about getting to your kids are no longer just adults.