Donggook has a quality time with the three children by going to a restaurant in his memory as well as making a promotional video for Pyeongchang Olympics. Meanwhile, Sam stays in a maternity ward with his wife, Yumi, and William for the delivery of his second child. You get to see the special story of them including the tough yet beautiful process of childbirth and welcoming the new member of their family with moving tears.

Donggook prepares a special fourth birthday for Sian who is transformed into a superhero. Sam and William visit the famous fastidious star, Jiwoong's house and finds a new generous side of him as an uncle. Meanwhile, Jiyong is surprised by how brave and confident Seungjae is in front of a crowd as well as in the nature.

Donggook has a special and awkward day with his father and Sian while wearing matching outfits. Sam takes a business trip to Japan and meets Sayuri to ask for babysitting as well as interviewing his idol. Meanwhile, as a farewell, Taeyoung's family opens Ki Cafe to repay the love they have received so far.

Donggook and the five siblings become runway models of a charity fashion show and experience the chaos of a backstage. Sam uses his wits to help William who gets exhausted while enjoying the food tour in Japan. Meanwhile, Jiyong finds enlightenment of raising a child through Seungjae's creativity test.

Hwijae and the twin become the cameos in Jinyoung's music video and the twin fall in love with tteokbokki and Jinyoung. Sam visits the neighbor, Jury, and practices being a father of two boys. Meanwhile, Jiyong disguises himself as a grandmother to find out Seungjae's honest feelings about him.

To celebrate the new year, Hwijae and the twins meet with the people close to Hwijae and exchange heartwarming greetings. Jiyong visits Yeonnam-dong with Seungjae and has an eventful day. Donggook, his parents, and his children visit the graveyard of Donggook's grandmother and savor the love of their family. Sam takes care of the two sons by himself for the first time and realizes the hardships and the joy of raising the children.

Donggook and the three kids collect the items they do not use and head to the junkyard. After they are back at home and Donggook goes out, the kids cause an unexpected trouble. Sam hears a shocking news about William's teeth growth when William and Bentley get different checkups at the clinic. Meanwhile, for Seungjae, who likes dinosaurs, Jiyong takes him to a special group meeting.

For Jiyong, who is busy at work, Donggook invites Seungjae over for a play date with Sian. Sam and Sam Okyere organize a 100-day photo shoot of Bentley. Meanwhile, Hyunbin spends the day with his cousin, Yoonji, and her lovely daughter Lani and reminisces the memories of the past.

Donggook's children are separated from their dad and spend the vacation in Bangkok while learning in an international school. Sian tries to adjust in his own way, to the new environment where he can't communicate with his own language. Sam gathers with three of his friends who also have kids and spend a good time. Meanwhile, Hwijae and the twins get down to cleaning the house for the spring.

Jiyong and Seungjae take a trip by train to Samcheok just the two of them. William's family gets ready to take off to Australia to meet Grandma. And Sam and Wiliam visit Dongdaemun Market and have a good time while picking up gifts for their family. Meanwhile, Donggook's children take fright at the unexpected "guest".

Jiyong takes Seungjae whose dream is to become a firefighter to the fire station after preparing gifts and a letter. Donggook's children visit Sian's new friend, Boise's home and spend a wonderful day with Boise's dad. Meanwhile, Sam's family finally reunites with the grandmother in Australia.

Seungjae has an internship experience for a day at Jiyong's company and becomes a tonic for the employees while helping Daddy. As Grandma spends a quality time with Bentley, William and Sam visit a safari in Australia. Meanwhile, Sian faces his biggest rival at the birthday party of Minchae, whom he likes.

Seungjae spends a great day with the fun Uncle Hyuksoo instead of Jiyong. Willam's family visits Uncle Paul and have a meaningful time while exchanging gifts and sharing good food. Meanwhile, Seoeon and Seojun's family make their farewells as they look back at the past memories.

Donggook gives it the first try at Zumba Dance with the children. Seungjae and Jiyong spend the day near the ocean and Jiyong loses his wallet. Sam goes on the last tour in Australia with his family and has a deep and meaningful conversation with his mother. Meanwhile, the actor Bong Taegyu's family newly joins the show.

Dong-gook and Si-an take a stylish stroll around a hip neighborhood in Seoul. The Ko duo are guests on a live radio show and attempt to plan a surprise. The Hammingtons have a play date with Boom's nephew. Tae-gyu and Si-ha have a photoshoot session with some friends.

Seung-jae babysits a pig. The Lee family stays at a guesthouse at Hanok Village and the siblings get separated. The Hammingtons have a playdate with Ricky Kim's family. Si-ha meets some friends at the park and overcomes one of his fears.

It's Children's Day, and the fathers have prepared special things for the kids. Ji-yong takes Seung-jae to the zoo. The Lee siblings get singing and dancing lessons, and the 5 siblings perform on stage. William gets a surprise from his favorite animal. Moon Sung-min takes on the 48 hour challenge.

Tae-gyu and Si-ha take the subway to visit a flea market. Chaos ensues in the Lee household as the 5 siblings plan a birthday surprise for Dong-gook. William and Bentley hand out popcorn around the KBS studio and Sam films a show. There's love in the air as Seung-jae attends a birthday party for Alice. Sung-min finishes his 48 hour challenge with the kids.

Ji-yong watches the Lee siblings, and Seung-jae and Si-an have a sleep over. Si-ha and Lani have a play date and visit a dry sauna. The Hammingtons watch a basketball game, and William shoots the ball.

The Lee siblings has a singer uncle over to watch them. Seung-jae takes care of his hurt dad. Bentley grows up right before our eyes, and Sam learns to cook. Jo Jung-chi and Eun-Yi take on the 48 hour challenge.

Jung-chi and Eun-Yi go on a hike and make music. They also have visitors over as they finish their 48 hours. The Ko duo commutes to Gwanghwamun. The Hammingtons visit Byung-jae, and together they go to YG studio.

Si-ha attends daycare, and Tae-gyu goes in a disguise. Plus, Si-ha's cousins come over. The Lee siblings go indoor rock climbing. The Hammingtons visit a countryside village and help out at a farm. Swung-jae meets a famous uncle from Taiwan. Plus, Seung-jae finally heads to Dokdo Island making a pit-stop at Ulleungdo.

Si-ha visits his grandparents. The Hammingtons become superheroes and visit Song Kyung-ah's house. The Ko duo continues their trip and finally touchdown in Dokdo Island.

The Lee siblings visit a mudflat and attempt to catch fish for their meal. The Hammingtons visit a mall and a waterpark. The Ko duo argues as they arrive in Taiwan. Kang Hyung-wook and Ju-woon take on the 48 hour challenge. Dong-gook takes the kids to Gauido Island.

Si-ha spends his second day at his grandmother's and attempts to catch crayfish. The Hammingtons go on a hike. The Ko duo spends their first full day in Taiwan, and Seung-jae meets up with Uncle Jasper. On their second day, Hyung-wook and Ju-woon visit a lake, and AOA members pay him a visit with their dog, Mochi.