I remember my Grandmother saying that the wind would change and your face would stay that way....haven't heard that for a long time...lol.  My 3 year old gives people grumpy looks when strangers talk to him but it's just because he is shy and doesn't know how to respond.  I always try to tell him say hello etc but i don't want to force him, he'll get there!

my son did the same thing at around the same age. I remember we were at a church breakfast and my husband got up from the table to get food. Matty saw his daddy leave and followed him. But along the way there were people who said hi to him and what did Matthew do but give all of them the dirtiest evil eye. LOL