Charlie bites Spencer and Teddy begins to worry that her baby sister is affecting their relationship. Leaving Ivy to babysit, she decides to surprise Spencer at work - only to discover a surprise of her own - Spencer with another girl.
Teddy prepares to try out for the school play with some help from her friend Alice. But things go wrong when Charlie draws in ink all over her face right before the audition. Meanwhile, PJ eats too much bacon and has nightmares that he's become too fat.
Gabe is left in charge of Charlie while working on a school project with his nemesis Jo. Meanwhile, Teddy must trick PJ into going to the dentist, but Teddy ends up breaking her tooth in the process.
Teddy takes a job walking dogs to earn some extra money. But, when she stops by Kwikki Chick, she winds up stealing PJ's role as the new model. Meanwhile, Bob is confident he can capture a mouse and Gabe seizes the opportunity to play a trick on Bob.
Spencer agrees to do a dance routine with Teddy for the school talent show, but when he realizes how bad of a dancer she is, he tries to fake an injury to get out of it. Meanwhile, Jo convinces Gabe she wants to help him run for class president.
PJ makes a funny video of Charlie farting, which becomes an overnight success on the internet. Meanwhile, Teddy meets Spencer's parents and loves everything about them and their neat, quiet house.
Teddy gets PJ and Gabe to help her throw Amy and Bob a surprise dinner for their anniversary. But when Charlie loses her favorite blankie, Teddy tries to track it down from the donation truck and PJ gets locked out of the house with Charlie inside.
In an effort to win over her English teacher and raise her grade, Teddy brings Charlie to class and dresses her up in various adorable costumes for a presentation. Unfortunately, Charlie has an upset tummy and throws up on Teddy's teacher.
Mrs. Dabney pays Teddy to watch her beloved cat, Kaboodle, while she goes out of town. Meanwhile, in an effort to find things in common with his crush, Gabe tells her that his parents are divorced and he's an only child living with his mom.
PJ gets a job delivering food for Kwikki-Chiki and falls in love with a customer. Meanwhile, Teddy tries to help out when Gabe is having trouble with Jo, a bully at school, but learns that Jo is actually a girl.
When Teddy discovers she has a Great Uncle Mel that Bob never told her about and refuses to talk about, she and Ivy visit the rest home where Mel lives and take him to a baseball game.
When Bob decides to cut down the tree that holds their childhood treehouse, Teddy and PJ stage a sit-in to protest. So, Bob wages war to get them out of the treehouse.
It's Charlie's first birthday and the family reminisces about the day she was born and everyone had to find a way to get to the hospital.
In order to get Amy to let her go to a midnight movie, Teddy pretends her mom is cool. The plan works until Teddy butt-dials Amy from her new phone, leaving Amy to overhear that Teddy was just pretending to have fun.
The manager at the local Redi-Mart is not amused when Charlie grabs a pair of baby sunglasses setting off the shoplifting alarm, so he puts Teddy and Charlie in holding until Gabe can devise a plan to bust them out.
Teddy asks Spencer to the school dance, and they double with Ivy and Emmett. The boys wind up in a "dance-off" but end up bonding, leading Teddy to feel Emmett has "stolen" her date.