I'm going to pull my daughters ear after she pulled the dog's ear.
Why do you think pulling her ear is a good idea?
They told me that it would make her stop doing it to the dogs.
Pulling a dog's ear is unkind and abusive. If you want to teach her to stop, then speak to her about it and not retaliate the same behaviour because it confuses the child.
Why can't I pull her ears, if I wanted to?
Children are not animals. You should not hurt or abuse them. If she has problems with the dog you should remove the dog from the situation.