Forgive me if this sounds daft but I think somehow that DD has been bitten and her nursery didn't realise/notice. I've raised it with them and they said there were no incidents and DD didn't cry out or seem upset at all yesterday. However she has a big red mark on her back which looks just like little teeth. I took a picture last night and again this morning as it is still very red. Is it worth showing the pictures to nursery and asking for a further investigation or am i going to have to just let this go as unexplained?