For live-in nannies, Saturday night sitters, and everyone who cares for kids. Answers to the questions sitters ask most: The parents want me to pick up their newborn every time he cries--won't that spoil him?A child who comes over for play dates always makes a terrible mess and never helps to clean up. What can I do?The girl I baby-sit for tripped and got a bump on her head. What's the best way to tell the parents?I take care of a six-month-old...