My daughter is 18 months and we go to this play group at the public library. She plays well with the other kids and loves following around the older kids. Recently a new girl joined the group. She is the same age as my daughter but bigger. She keeps picking on my daughter, pulling on her hood and pushing her. Today she got a scrap on her head from the other girl pushing her to the ground. It’s totally unprovoked. The girl’s mom doesn’t do anything and just saying her daughter is really friendly and wants to be friends. My friends don’t shove me. My daughter keeps running away from her but the girl keeps following her. I’m not sure what I can do... other than tripping the girl (j/k).