I have two girls that are 11 months apart. When my oldest does something that I don't like I started growling at her. She would stop before she was really in trouble. Now she has become used to that and she just laughs at me. Well she was playing near a toy and my youngest one went to the other side of the toy. She was just standing there looking at my oldest. All of a sudden I hear growling!! I heard it again and started looking for the dog. The dog was asleep and I realized it was my oldest growling at her sister. What really made me laugh was when the youngest started growling back!!