A perfectly normal one. "Preschoolers are just exploring the notion of 'friend,' and what it means to have people who are important to them outside of mom and dad," says Linda Mayes, M.D., a child psychoanalyst at Yale University. At the same time, they're figuring out how to treat their peers and testing them to see what makes other kids happy, angry, or sad.
That may be comforting to you, but what about your child's pain? To help your preschooler handle a friendship that runs sweet and sour:
WAIT IT OUT Suggest that the offender didn't mean it when she made the cutting comment. A 3-, 4-, or 5-year-old who blurts out "You're not my friend anymore" is often motivated by momentary anger or frustration over not getting her way -- the verbal equivalent of a 2-year-old grabbing a toy from another child. Chances are, by the next time the two see each other, they'll be best buddies again.
GO TO A HIGHER AUTHORITY When clashes occur at preschool, you can bring them to the attention of the teacher. She should keep an eye out for volatile situations and defuse them as they arise. For instance, she might use "circle time" to talk about how friends should treat each other, or read a story about hurt feelings.
PROMOTE THE SILENT TREATMENT If your child learns to remain silent or to walk away when a friend taunts her, chances are good that the problem will evaporate. "Silence will help extinguish the behavior, because the comments don't have as much power if they're not getting a rise out of the intended target,'' says Nadine Kaslow, Ph.D., a child psychologist at Emory University, in Atlanta.
TEACH HER HOW TO RESPOND Provide the words your child needs to stick up for herself, but keep them positive, or at least neutral. Tell her to say "I know you didn't mean that" or "Well, you're still my friend," instead of "You're not my friend either!" or "You're not the boss of me!" Then, to reinforce the message, act it out: Use the other kid's hurtful words, and have your child practice responding with the phrases you've taught her. "The earlier you can help children learn ways to cope," says Kaslow, "the less traumatic this stuff is."