three year old biting

My daughter has been biting on and off for the past two years.   She bites blankets and stuffed animals when she is excited.  She bites me and her dad when she is excited and she used to bite us when she was mad.  The problem is that she bites her best friend who is the same age when she is angry (usually when they have both hands on the same toy).  She seemed to stop altogether around 2 1/2 and has recently started again but only two times in the past few months. Her parents are on the verge of not letting them play together.  Is this behavior developmental or is there something else going on?

[stepmother]

Your daughter and Freud would get along. The oral stage of development. Very normal to some degree. They say when kids bite it is a release of emotion. Since, she has moved from blankets to toys to people... She needs to be taught (through modeling) a more appropriate way of expressing herself. When she bites out of anger you need to give the attention to the victim and she needs to give it. For example, holding the ice on the bite ( you do this with her hand over hand) teaching empathy may help stop the problem. Kids will repeat behaviors that have worked for them in the past. So if you want to replace behavior teach a new one. I would not spend too much time talking about her biting or she will get the hint that it is really attention getting. Make it known that this is not okay and focus on good behaviors.