Hi Janet... I've got a son that's just turned 5 and a 5 month old pup that's STILL biting him!!!!!!
It's very tricky with kids of that age, my son does stand still but you can't tell a 4 yr old to stay that way when they have fangs in their legs. It just takes one squeak or twitch from the kid and the pup's got a reaction and that's all he needs to carry on. Sometimes it works and is the best thing for the kid to do before you get to them to intervine but it's not a full solution at that age. I had a free home visit from the lady that ran our puppy classes and she said that for the most part, it's best to keep young kids and puppies separate until the pups grow out of biting and only let them play together when you can fully supervise. She also suggested putting a long lead on the pup and when he gets nippy calmly pull him away and remove him and put them in a 'time out' space. So basically nipping = no play. Having tried other things, I have to say I think it's the best solution and leads to less friction and confrontation. Slowly our pup is able to stay in the same space as my son for longer periods but he still needs removing frequently. I have a baby gate across the kitchen and that's where I put the pup when he's biting, he can still see everyone but can't play.
Leaving them together all the time was just a game for the puppy - no amount of 'ah ah' and standing still worked for that long but he's learning that if he wants to be 'with' us and not in the kitchen, he must not bite and my son is suffering a lot less too!
Good luck it will take a while longer yet, but will be worth it in the end
Hannah x
