Alex and Sara are worried. Their daughter Lee starts school soon and they think her best friend Ernie is going to be a problem. It isn't that he is badly behaved or mischievous, the problem with Ernie is that he is imaginary. They hatch a plan to force their daughter to grow up and to get rid of Ernie. But as the plan begins to work they learn a lesson that parents usually have to teach their children - be careful what you wish for.