Thank you all for your input. So far this girl is not getting the other girls to do it with her. The girl that is jealous is just focusing all her attention on another girl in the group. The other girls are not turning against my daughter, at least not yet. I get the feeling the jealous girl is a one-man band with this. She has decided to turn a cold shoulder towards my daughter, but is has gotten very close to another one of the girls in the group. The jealous girl will only interact with this other girl and is ignoring my daughter and the others.

I've been thinking about having my daughter handle this as a diplomat would. I thought about telling my daughter to politely confront the jealous girl and straight out ask her about her behavior and inquire as to what the problem is in an effort to salvage the friendship and to let the jealous girl know that her behavior has been noticed and make her account for it. What do you all think of that?