In the past week my 8yo son has asked about rape, semen, sex and how HIV is transmitted - triggered by school discussions and newspaper articles. Last weekend I left him playing a game on the Internet and later saw he had accessed sex and porn sites. Last night he sat down in from of the tv and started masturbating. I answered his questions, he denied hed accessed the sex sites on the Internet (wasn't certain it was him) so I told him that they were not appropriate and instituted parental controls, and simply sent him to bed last night....didn't know quite how to react. He hasn't lived with me for some of the year during a custody issue, so not sure if this is age appropriate or if I should have concerns. Please advise, thanks.