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 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. 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?
Erin and Aaron clash over Saturday night traditions: Erin wants pizza and Aaron wants sushi, and they will do anything to win! Meanwhile, Chuck and Natasha have a special daddy-daughter day planned but struggle to find a shared activity they'll both enjoy.
While Chuck and Sylvia take a vacation, Erin and Aaron convince their parents to let them babysit Natasha, not realizing how much trouble she will be.
Erin and Aaron are excited to compete in the music competition between band and chorus with the winning team getting a trip to New York City. Erin's laid-back ways causes Aaron to kick her out of band, driving her to battle it out by joining chorus.
Erin and Aaron decide to have a sing-off to see which one of them gets to keep their first name. When Aaron loses, Erin pushes him to adopt a new country persona to match his middle name. He soon over-commits and Erin needs to help him remember who he is.
Erin invites Aaron’s old teammates to visit him, not realizing Aaron never told them about his love for music. When Aaron lies to his friends, pretending he only cares about football and pranks, Erin has to convince him to come clean.
After Aaron urges Erin to bond with Sylvia, Erin and Sylvia start spending lots of time together making Aaron and Chuck feel left out. Natasha tries to gain power at her school by having Vivian and Hunter impersonate Erin & Aaron.
Natasha plans an elaborate photoshoot for the family’s moving announcement. Erin and Aaron fear the pictures will be a social disaster. Meanwhile, Sylvia and Chuck lose Captain Cutie Pie and go to great lengths to win her back.
While Erin struggles to get a date with her crush Cayden, Aaron has money trouble for a date with his crush Lily at an expensive restaurant. Erin and Aaron decide to be “in cahoots” and come up with the ultimate plan to land them their dates.
When Erin and Aaron upload their songs online to choose which one to perform together at Asbury Park’s “Porchfest”, a Grammy-winning producer reaches out with a life-changing offer... for one of them.
