When the Short family arrives at their vacation resort in the Yucatan, their accommodations aren't quite what they expected. Also, Heather is ridiculously overprotective of Sophia during the family activities; Jen and Greg discover that Matt and Colleen have been duping everyone; and John and Joan get separated from their tour group in the jungle.
When Colleen and Matt try to impress a potential birth mother, they have a hard time competing against another rich, swanky couple. Also, Jen's pregnancy takes a toll on Greg; Heather lets John take credit for her housekeeping while Joan recovers from knee surgery; and Tim arranges for Tyler to record a demo at a friend's studio.
While Joan is bedridden recovering from surgery, she persuades Sophia to spend time with her, which she quickly regrets. Also, Jen and Greg select a name for their new baby only to learn that Matt and Colleen chose the same one; Colleen and Matt invite the family over to get to know Morgan; and Heather has a new business idea.
When Colleen and Matt learn they may not be allowed into the delivery room for the birth of the baby they are planning to adopt, they try to convince Morgan to have the baby at home. Heather is thrilled when Samantha has a falling-out with a friend who was a bad influence. Jen thinks Greg bought her a beautiful present only to discover it wasn't for her. John encourages Tim to see a cardiologist.
After Tim has a heart attack, he becomes super clingy and annoys the entire family. Also, Greg and Jen make a pact to keep their baby's gender a secret; Sophia's new pet frog turns out to be a dangerous species; and Matt and Colleen receive news about their impending adoption.
After John befriends the janitor at Sophia's school, Mr. Sissel (Biff Wiff), John learns that Sophia and her friends believe a childish rumor about him. Also, Heather pushes Tim and Joan to go for walks together while recovering from their health issues; Matt and Colleen try to tame Dougie's (Fortune Feimster) bad habits; and Jen is desperate to not go into labor during Lark's birthday party.
Greg scrambles to find Lark when he loses her at the hospital while visiting Jen and the new baby. Also, Heather offers to help Sophia with her math homework but can't figure out the new teaching method; Matt enrolls his adopted son, Lucas (Vivaan Bisoi), in a father/son art class; and Colleen organizes a family photo shoot and glams Joan up for the occasion.