DS1 aged 7 has been using my iPad for homework.Quick flick through history reveals he has seen some porn sites,first accessed by him searching for "Simpsons naked."Then obviously has seen other things and had a look at pornhub, fit chick teenage fuck and other similar.I am very shocked and don't know how to deal with this.I asked him what he had been doing with the iPad and he said he didn't want to tell me.When he realised I knew,he cried ,said he felt embarrassed and got upset.Quick chat about not looking at things unsuitable for children ,have obviously changed security and restricted iPad use and left it at that for now.What else should I do? We have never even had a facts of life discussion other than in biology/animals mating context.I think it was childhood curiosity initially but am worried about exposure at this age and whether I should talk more? Am also sad that I have let in happen by not being careful & supervising .Any advice?