Erin and Aaron's first day as stepsiblings 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 through the only thing they have in common, music.

Aaron sets out to find a girlfriend to break his heart so he can write a hit song. But 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. Can Aaron fix it with a song?