Arthur is a happy, smiley, content baby. He's really laid back and hardly ever whinges (except at night if I'm doing sleep training!!!) But, he has this thing where he screams really loudly - sometimes it seems to be in excitement, sometimes to get your attention. It drives me Bonkers and it's embarrassing sometimes in public. He's 7 months old, so I know they experiment with different noises, but I need to nip this in the bud NOW!! any suggestions?