:) All 3 of my boys did this. It's to be expected especially in a child around 1 year of age when they're in the teething stages. Babies don't understand at that age that it's painful. In most cases it's probably just another type of communicating for them, or their way of playing. It really shouldn't cause worry for future behavioral problems unless they're older and understand that it's wrong and hurts. When they do it out of aggression in other words. The best thing to do for me was a firm NO, and maybe a time out. It really hurts a baby's feelings to hear that tone of voice or to be sat in time out. Don't give the biting any positive attention, like laughing because they'll take it to mean they can get good attention this way. Also, be careful not to even play bite with babies because they can't tell the difference from that and them wanting to play bite someone else.