Erin and Aaron's first day as step siblings and they are in no mood to get along. But when they discover that their differences may lead to a family break-up, they must find a way to come together.

Aaron finds the perfect replacement for his beloved broken piano but the shop owner, Mr. Ledder, has a history with Erin and refuses to sell the piano to an instrument killer like her.

Aaron sets out to find a girlfriend to break his heart so he can write a hit song, that girlfriend turns out to be Erin's BFF, Vivian; Erin tries tricking Vivian into breaking up with Aaron but ends up betraying her trust.