When Rachel apparently misses out on an incredible educational opportunity, her sisters are suspicious of how well she takes the news. Meanwhile, Ethan cashes in on his experience of living with four sisters by landing a job.
As Harley tries to raise money, by running a day camp for the neighborhood kids, in the Diaz backyard, she finds herself distracted by the new neighbor, Ellie's irritating cousin, Aiden.
Under Abuela's watch for the weekend, the Diaz kids are committed to making her visit disaster-free, that is, until Harley learns that Ethan spilled her deepest secret.
Spring vacation, here the Diazes come. The Diaz's must deliver a luxury yacht. They live it up until they dock at the port next to the dreaded Pillman family.
Harley learns that her opportunity to meet one of her scientific heroes depends upon her ability to rein in Daphne. Meanwhile, Ethan faces some hard decisions in forming a band for the Marshport Seafood Festival.
Harley noticed the Diaz kids aren't as tight-knit lately, so she uses her Lock Squawk invention to turn the attic into an escape room and acts as the game master.
Harley realizes that she had a great time hanging out with a surprisingly sweet and generous Aidan, despite a chaotic day. Georgie calls her out for crushing on Aidan.
When the family car rolls into the garage and causes severe damage, Tom and Suzy look for a culprit; Ethan and Harley don't have alibis, so they head to Diaz Court.
Harley discovers that the confusing circumstances surrounding the time she was born literally cost her dad the vehicle of his dreams, now more than fifteen years later, she attempts to rectify the situation on his birthday.