This Is Us Killed Off a Major Character in the Penultimate Episode

We knew this was coming—but it didn't make it any easier.

After a lengthy battle with Alzheimer's, Rebecca (Mandy Moore) passed away during the May 17 episode of This Is Us. With only one week before the May 24 series finale, Rebecca's death felt inevitable. Nonetheless, we hoped that Rebecca would make it one more week heading into the penultimate episode. But our hope did not last, and neither did our supply of tissues.

At the start of the episode, a younger Rebecca found herself on a train—just like the one she used to take into the city with her dad on Sundays. As her health took a turn for the worse in real-time, she began to interact with deceased people from throughout her life, including second husband Miguel (Jon Huertas), Dr. K (Gerald McRaney) and Randall's biological father William (Ron Cephas Jones), who guided her through the train.

When it came time for sons Randall (Sterling K. Brown) and Kevin (Justin Hartley) to say their goodbyes, the two swapped stories about their mother. At the same time, the memories that the they discussed visualized on the train for Rebecca.

Kevin confessed that he thought a pro baseball player had a crush on their mother at an autograph signing, and Randall didn't need any proof. "Everybody had a crush on mom," he said.

All of Mandy Moore's This Is Us Ages

As William attempted to get Rebecca to enter the final train car, she stopped and said, "No, I told you I'm waiting for someone." That's when Kate (Chrissy Metz), who had been hustling to get back from a trip in time to say goodbye, made it to her mother's bedside.

Kate tearfully told her mother, "I'm here. I love you, Mom. I love you so much." When Rebecca heard Kate's words over the train's speakers, she knew that Kate made it, giving William the go-ahead to enter the final car.

With tears streaming, Randall said his final words. "I want to say the perfect thing to you, Mom. But I'm not sure what that is," he said. "I don't even know if you can hear me. I love you, Mom. We're good now. You made us good. Thanks for all the meals. Thank you for always making us feel loved."

In the train's caboose, William gave his sage wisdom to Rebecca about death not being the end—but rather a brand new start.

"If you step back and look at the whole picture, if you're brave enough to allow yourself the gift of a really wide perspective," he encouraged her, "if you do that, you'll see that the end is not sad, Rebecca. It's just the start of the next incredibly beautiful thing."

William then left Rebecca alone and...it happened. She lay down on a bed and next to her, of course, was first husband Jack (Milo Ventimiglia). The two said a simple "hey" to each other because, after all this time, what else needed to be said?

The episode also introduced us to the Brooks family, with patriarch Dulé Hill. In a flashback car crash, his son Marcus was critically injured. It just so happened to be the same night that Jack died due to smoke inhalation after setting the Pearson house on fire. Before Jack passed away, however, the two fathers had a chance encounter, in which Jack gifted him with Dr. K's advice from 18 years prior: "There's no lemon so sour that you can't make something resembling lemonade."

We later learned that Marcus, who survived, went on to to create a landmark Alzheimer's drug, the disease that took Rebecca's life.

We'll need some time to recover, but in the meantime, we'll use the wise words of William to carry us forward: "If something makes you sad when it ends, it must have been pretty wonderful when it was happening."

The series finale of This Is Us airs May 24 at 9 p.m. on NBC.

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