My friend has a Golden Retriever. The dog is 2 years old and is not a bad dog but has issues. She has never had any type of obedience training and definitely needs it. Yesterday she bit a child visiting the house and it wasn't the first child to be bit. It wasn't a case of the dog bouncing around and a tooth happened to hit the child hand. She (the dog) did a low mean growl and then bit the child without any provoking. She didn't break the skin but did leave teeth marks. Can any suggest a good dog trainer in Suffolk county?