Plus, find out who from the cast knows how the 39-year-old actor's beloved character dies.
This Is Us doesn't just have the fans in tears.
During the show's panel at PaleyFest at the Dolby Theatre in Hollywood, California, on Saturday, Milo Ventimiglia got emotional while explaining who he draws inspiration from in his real life when tapping into his character, the beloved Jack Pearson.
WATCH: 'This Is Us' Finale: Jack and Rebecca's Marriage Suffers Its Biggest Hit -- Is it Over?
"Here we go, you're going to find me crying," he confessed. "My father."
The 39-year-old actor pointed to a specific spot in the audience, revealing to fans that his parents, Peter and Carol, were actually in the crowd.
"[This Is Us writer] Dan Fogelman and all the producers and writers wrote this man who loves his wife and loves his kids, really as simple as that," he said, as the tears began to fall down his face. "And I saw that in my own father."
"There's not a moment in my life where I don't think about how he raised us, my sisters [Laurel and Leslie] and I," he added, as the crowd erupted into cheer. "So, my dad."
Naturally, there wasn't a dry eye in the audience after that precious moment.
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As fans of the popular NBC series know, there's a point in time where Jack dies. Although many were hoping for that reveal during the season one finale earlier this week, it didn't happen – we have more clues, but we still don't know exactly when or how the Pearson patriarch passes.
But while chatting with ET on the red carpet at the event, Ventimiglia revealed he does know how Jack eventually dies. In fact, the majority of the cast knows, too!
During the panel, we learned Justin Hartley (Kevin), Sterling K. Brown (Randall), Mandy Moore (Rebecca) and Susan Kelechi Watson (Beth) are just a few of the cast members who are in on the big secret fans are going crazy over trying to figure out on their own. They re-enacted their reactions to the moment they found out Jack's fate, which you can see in the tweet below:
One thing we do know about season two, however, is that fans will hopefully start to like Miguel, Jack's best friend who later ends up with Rebecca once he's out of the picture. In honor of that, the cast and crew took turns saying one nice thing they appreciate about the character most fans love to hate. See their answers (some serious, others clearly a joke) below:
Executive producer Jon Requa: "He has a lustrous head of hair."
Executive producer Glenn Ficarra: "I forgive him for killing Jack."
Ron Cephras Jones (William): "He married Rebecca."
Susan Kelechi Watson: "He wore the [pilgrim] hat."
Sterling K. Brown: "You know what? Before William, he's the only grandfather that our daughters knew, and he's treated them very, very well."
Milo Ventimiglia: "I'm going to give him two quick things. One, he gave Kevin some confidence. Two, he was always there for Jack in his tough situations ... he's there for people."
Mandy Moore: "He's clearly compassionate. He was there for Kevin in his moment of need."
Justin Hartley: "Yeah, I would say he's definitely there for people ... he continues to show up which is kind of nice, and we all hope we have people like that in our real lives. And in my real life, I know the man who plays Miguel, [and] he is one of the nicest [people] ever."
Chrissy Metz (Kate): "Did you see the Christmas decorations? I mean, he went in. It was incredible. I appreciate that, and he did it with such excitement and enthusiasm. I love that."
Chris Sullivan (Toby): "He's the only person that will speak Spanish with Toby. One of Toby's great loves."
Gerald McRaney (Dr. K): "I'm going back on lustrous head of hair."
Jon Huertas, who portrays Miguel, made a surprise appearance at the panel, telling the crowd that despite how some fans feel about his character, Miguel is "a character and a very important character."
"We'll get to see what happens with Miguel, I think, later on," he said. "Hopefully he'll prove he's just as dedicated as a husband as Jack."
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