It's kind of hard to terminate when it's your 'own child'! Yes, mine is the biter. He started around 14 months and when he would bite I would tell him 'no-biting' and put him in time out. It took about 2-3 weeks, but it stopped. He started again last week, 3 days in a row! I must say he has a molar coming out (first one). All the times he's bitten the other little dck is when I'm physically out of sight. eg. I went to the washroom, same floor and a few feet away from where they were playing - less than a minute! Another was when I was in the kitchen prepping lunch, couldn't see them over the counter and it happened! I also notice that he does it when something is taken away from him, or he gets frustrated with the other dck as the other one is bigger and stronger & mine is on the little side...that's no excuse, but I've found that those are the reasons he does it. So in the last few days, I've been keeping his teething ring ready for when I notice it going to happen and make sure I can always see him. If I need to go to the washroom I make him stand right outside!!! Seems to be working...thank you all for your advise. Hoping it'll stop soon!