As their paths cross and their life stories intertwine in curious ways, we find that several of them share the same birthday and so much more than anyone would expect.

Rebecca makes a surprise visit to Randall's home where she encounters his biological father, William. Kevin anxiously decides to take the plunge and move to New York to pursue a Broadway job, with the expectation that his sister, Kate, will move with him. Toby is determined to get Kate out of Kevin's shadow. Jack and Rebecca take home their babies from the hospital and adjust to the new life of parenthood, while coping with the loss of their other child. Rebecca struggles to connect with their adopted child and searches for answers.

The Pearson family finds themselves at the hospital on Christmas Eve after little Kate comes down with appendicitis. When they run into Dr. Katowski, who is alone at the hospital, they realize they need to be there for him as much as he was once there for them. Presently, Kevin celebrates Hanukkah with Olivia and her family, Kate continues to pursue her big surgery and someone from William's past reappears in his life.

Kate struggles with her feelings in the aftermath of Toby's heart attack. As William begins to spend more time with Jesse, Randall has to get used to his father's new relationship. After receiving the news they're expecting triplets, Jack and Rebecca must find a way to afford a home that can accommodate three babies. Olivia unexpectedly resurfaces, throwing both Kevin and Sloane for a loop.

As the birth date of her triplets quickly approaches, a frazzled and emotional Rebecca forgets Jack's birthday. Dr. Katowski struggles with the loss of his wife and wonders how he'll be able to continue on with his life without her. Joe, the firefighter who delivered baby Randall to the hospital, fights to save his marriage.

Rebecca finds solace with an old friend as the Pearsons struggle to cope with tragedy. Jack teaches Kevin and Randall to drive.

Deja's life with her mom, Shauna, and great grandmother Joyce unfolds from the very beginning. Randall and Beth welcome visitors to their home.

The Pearsons gather to celebrate Baby Jack's first birthday.

The Pearsons gather around Rebecca's bedside.