At the moment as I type my DS1 who is 4 1/2 has his friend over to play and his friend who is just 4 has, I suspect only by my nose and knowing he's done it before at home, soiled himself. He denies doing it and I don't want to push him on it as he is not my child and it is a bit of a sensative issue (he's been potty trained for 1 year). Any suggestions? At the moment I am just letting them play but DS1 keeps saying 'I can smell poo mummy!' I guess I should just leave them to it and tell his mum when she comes to pick him up.