Sometime around the six-month mark, but perhaps as early as four months or as late as eight, your baby will, for the first time, get upset when you try to hand him over to a stranger. Stranger anxiety will make your life more difficult for a while, but it is an important developmental step. It means that your baby has figured out that his mommy, daddy, and the other people he sees every day are different from everybody else in the world. He knows that food, comfort, and fun come from these people and he doesn't want a substitute.

You can get through stranger anxiety best by giving in to it. Warn people whom your baby doesn't see often to approach him slowly, or recommend that they sit across the room, ignore him for a while, and wait until he approaches them (or, if he's not mobile, shows interest in them) before coming closer.

You also need to monitor your emotions to make sure you're not sending the wrong message. When a stranger approaches you in the grocery store to comment on your beautiful baby, do you clutch him tighter, or do you smile and tell your baby, “That nice lady thinks you're sweet?” When you hand your baby over to a sitter, make sure it's a sitter you feel comfortable with. Always say good-bye if you're leaving your baby in someone else's care. If you sneak out, you might get away easy that one time, but you'll pay for it for months. After your baby comes to trust that you are not going to give him to a stranger and realizes instead that these people are just more fun faces to gaze at, stranger anxiety will pass.