ds aged 5 in the bath tonight got angry with his sister aged 2 after she had swept away his foam letters from the side of the bath . he normally would say something but tonight he grabbed hold of her arm and bit it . i reacted by getting him out of the bath getting him dried and put him straight to bed (it was six thirty when it happened) .i have just checked my dd arm and the bite mark is still there. anyway advice wanted please first time this has happened