have trouble telling the difference between dangerous and annoying. (Is jumping on the bed dangerous, for instance?) When he comes to you in order to protect someone, praise him: "Thank you for looking out for your brother. That will help keep him safe." This way you avoid the sibling rivalry trap, focus on taking care of the child in need, and also keep a source of vital information open. Don't give in There are lots of situations, of course, where safety isn't at stake. In these cases, if you punish the other child you'll reinforce the tattling. By telling on someone, your preschooler is drawing you in to whatever power struggle he's involved in with his friend or sibling. If you take his side, not only will you reinforce the behaviour by helping him achieve what he wants (that is, he gets your attention and the other child gets into trouble), you'll also risk disciplining the other child unjustly if your youngster is exaggerating his playmate's crimes, which children often do. If you refrain from jumping in, your preschooler will soon understand that some battles are meant for him to tackle by himself. Increase the cost of telling tales Give your preschooler some work to do when he tells tales. When he comes running to you with news of his sibling's dastardly (but not dangerous) doings, for instance, you might tell him to draw a picture of the deed and leave it on the table, where you'll look at it