Friendship battles among children have existed since the words 'you can't play with us' were first uttered in the playground. But the worry is that today it seems there is no minimum age limit to being hurtful to others. Unkind or exclusive behaviour appears to be starting sooner than ever ? even in nursery school. As a result, friendship issues top the list of parents' concerns, and, from the other side of the school gates, they can often feel powerless.