My son came home from a morning at nursery today and when I changed him after his nap I discovered two scratches under his testicles, in a sort of separated V shape. No-one at nursery said anything to me and he didn't have any marks there before we left home this morning. I feel really upset that someone did this to him and did not let anyone know, I trust them to be careful with him. I'm going in to talk to them tomorrow but I'm really not sure how to approach this, should I put anything in writing or just talk to them at this stage???