she's most likely reacting to the change in the home and isn't able to productively express her feelings about what's going on. my son started biting my dd when she was about a year and started crawling/cruising. he was frustrated with the attention she was getting and frustrated that she was all up in his business after being stationary for so long. that actually lasted a while but eventually stopped. she is 3 and he will be 6 next month and i can't remember the last time he bit her. he's just an oral kid and it's his go-to emotional release. it's just something we had to work very hard on, try to head off but then punish for when it happened.
Please don't bite back =(. Kids bite for so many reasons. A new baby is a big one. The best thing you can do is show the older child that you do see them and that they are still very important to you. Praise them often and ask if they can help you with simple tasks like feeding or bathing the baby. Take time out to spend with them alone and with no mention of the baby. It is a tough transition and it can be hard for young kids to communicate their frustration. Just be patient and firm about the biting. This too shall pass.
I have a daycare for 10 years now and this is the first time i have ever had a "bitter"! she is only 16 months and she is quick at grabbing/latching onto the kids and bitting them. She not only bites, she knows how to pinch. But this little girl just started walking and recently introduced to the playroom. she just started interacting with other children. I always felt that bitting was a learned behavior. No one in the daycare has ever even come close to bitting, fighting or even taking a toy from her. All the kids adore her and give her toys to play with. But once she sets her eye on a toy and if the kid doesnt give it up, she will bite them, grab them and pinch them. Kids are going home complaining now so i have to do something constructive.
I cannot bite the child back or hit the child in the mouth, which are the only advice that i hear will stop a child from bitting. Does anyone have anyother suggestions. Help