My just turned 3 year old son is a pleasant, polite child except for when he is saying "hello" and "goodbye". At these times, when people greet him, he will turn his head abruptly away and make a rude "hmmp" sound and close his eyes really tight. He sounds like a whiny, rude brat when he does this. It's so unlike how he is 95% of the time, I'm not sure how to handle it. He has told me he doesn't like people to say "goodbye" to him because he doesn't want to go. This sort of makes sense, but family and friends are a bit put off, I think. Any suggestions?