"This Is Us" dropped another final moment bombshell on viewers.

At the end of the Season 2 episode appropriately titled "Brothers," it was revealed that Jack Pearson had a younger brother named Nicky. When both Pearson boys were waiting for their drunk dad to get out of a bar and take them camping, Jack told Nicky he'd never leave him. We also saw older Jack looking through Vietnam photos, and we saw Nicky again.

It looks like Nicky probably died in Vietnam. This is the first fans have heard about Nicky, and Jack never told his own wife Rebecca or their kids.

The Hollywood Reporter asked episode directors/executive producers John Requa and Glenn Ficarra about Nicky:

THR: Why wait to reveal this Nicky character and why was now the time to do so?

Glenn Ficarra: Nicky lives large in Jack's past and it ties into Jack's psychology as we explore the issues that maybe contributed to his alcoholism.

John Requa: And the exploration of the man and who Jack was and the ripple effect through time to his children and the people he affected in his life. In an effort to fully understand him, Nicky is a big part of that; that story from their past and how they ended up in Vietnam.

THR: Why make it a reveal at the end of an episode rather than introducing it at the front and devoting an entire installment to the story?

Requa: We're going to meat that story out. It's just going to come out in drips and drabs. What they're really getting at are the larger themes of, here's the best of the man, as manifested in his son Randall, and a courage with the Deja relationship, and then here is also the bad side of the man in his son Kevin, who is dealing with his addiction and keeping secrets and lying. The reveal at the end really makes the link. Here's where this comes from. This is a manifestation of this part of Jack. That's how it works in the composition of this episode.

Entertainment Weekly also asked John Requa and Glenn Ficarra some Nicky questions:

EW: So Jack has a brother, Nicky, who we assume died in Vietnam. Why has he hidden this information from Rebecca and the rest of his family? How did his death impact Jack?

Ficarra: Jack, as we're showing this season, has an ability to emotionally compartmentalize things, and his relationship with his father and brother, those are definitely related. He has a tendency to keep in a secret, which is manifesting itself in his son, Kevin.

EW: Jack's Vietnam mystery deepens a bit here. After seeing images of him hopping out a helicopter with an M-16 earlier this season, we get the sense that there's a lot more to his story than just being a mechanic. Will we find out this season how Jack lost Nicky in Vietnam — and what unprocessed emotions he is carrying from that?

Requa: We can't get into the details, but clearly this looms large in the person that he is. The big thing is that he keeps secrets, that he has compartmentalized and hidden away this part of his life, which obviously was his brother, and it was a big part. Obviously a major thing happened, some trauma of some sort. And that's what Kevin is doing. That's what we're trying to say with this episode. [...] And it also explains why at the beginning of the episode, Jack is almost a little possessed by his desire for Kevin and Randall to work out their relationship problems, and it's not until the end of the episode you're like, "Oh, geez, so that's why it's so important to him."

The Powers That Be previously said Jack's Vietnam story would be a slow build and be a bigger part of the future of the show, after we finally get answers on that fire.

"This Is Us" airs Tuesdays on NBC.

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