What Causes Twitching In The Face And Hands?

Hi, may I answer your health queries right now ? Please type your query here...I have a 3 yr old son who randomly has twitches in his face and hands. At first it was just hands and recently it has been in his face. He only seems to do it when he is not busy or occupied with something. What could cause this? I am wondering if it has anything to do with seizures as it runs in his dads family...