Thanks for posting this thread. I'm also dealing with a new neighbor's kid who's 5 years old and is such a bully. No matter how old you are, he'll just do whatever he want to you! It's unbelievable!
I had a little neighborhood gathering at my place and all the adults witness him throwing sands in a one year's old baby boy. He then told everyone that the baby started.
He was put in time out from his mom but it doesn't seem to have any affect on him.
I'm now avoiding him. I don't want my son to pick him his bad behaviors. His own father told us that he's having a difficult time dealing with him. His mother tries but not very successful. Sad!