to me this reads as if one is making faces to a stanger's baby when the stranger's parents arent looking. so this would only work if the baby's grandparents are present and not looking at the one making faces.
Let's face it. Some people aren't the sharpest tool in the shed. They do stupid things and we get a kick out of it. If you love fails, silly pets and people doing the dumbest things, you're in the right place. It's time to get stupid!