I had a group like that for a few years with an obvious leader in the pack directing the play and when he went to JK last year the boy left behind couldn't even use his own brain, I swear! He was 3 years old and was used to having the leader tell him what to play all day and it took months of him just sitting there like a lump and my encouragement before he learned that he was the oldest and able to choose the activities and play with anything he liked. But in the past year he made fantastic improvements before he just went off to JK too.