‘Whoa Didn’t See That Coming’: This Is Us Cast & Fans React to Mysterious Family History of Jack’s Brother

People goes over the revelation that came out in yesterday’s episode of This Is Us, Brothers.

[Spoiler alert: This story contains plot details from Tuesday’s episode of This Is Us, titled “Brothers.”]

This Is Us fans and viewers got to see more glimpses into Jack Pearson’s past on Tuesday night’s episode, specifically his family before the Big 3.

In season 1, we met his abusive alcoholic father, Stanley Pearson (Peter Onorati), and saw a moment of Jack’s military service in the Vietnam War. And now, in the sophomore season, we see that Stanley may die of cirrhosis without saying a final farewell to his son. In addition, we learn more about Jack’s life as a soldier.

Tuesday’s episode revealed that Jack had been hiding a major truth about himself for the past decade: his brother Nicky. (Nicky could be the reason why Jack wanted his sons Kevin and Randall to get along.)

Flashbacks showed Jack with his younger brother waking up from the backseat in a car and putting on his black-rimmed glasses before the older sibling said, “Don’t worry Nicky. I’m not going anywhere, I’m not going anywhere.”

Then the scene fast forwarded to adult Jack looking through a memory box filled with dog tags and old photos from his military days, including a group picture that showed Nicky wearing glasses and a nametape that read “Pearson.”

Previously, during the second episode of this current season, titled “Manny-Splendored Thing,” we saw the blades of a helicopter as the camera panned down to show two men in full Army attire jumping out of the aircraft. One of them was Jack, who was wielding an assault rifle.

And during the first season, fans and viewers saw Jack transition from Army vet to neighborhood mechanic. Remember when Mrs. Peabody asked Jack: “How did you come back from Vietnam so nice? Seems like most of the boys lose their damn minds over there.” And Jack told her, “I was just a mechanic. You know, maybe we had it a little easier over there.”

Well, it appears Jack wasn’t just a mechanic.

Fans and stars Sterling K. Brown and Chrissy Metz reacted to Nicky on social media with many wondering how much of an impact he could have on Jack’s life.

“Jack and Nicky, brothers, soldiers in Vietnam. Looks like there’s more to Jack’s story than he let’s on,” Brown live-tweeted during the episode.

“Niiicky! I must know everything, now!” Metz live-tweeted.

Mandy Moore also took to Twitter to share her reaction to the surprise twist. “Whoa. Didn’t see that coming. Introducing Jack’s younger brother, Nicky,” the actress wrote.

And fans couldn’t believe there was another Pearson family introduction.

While we have more to learn about Jack and Nicky’s brotherly bonding, next week’s episode will give viewers an in-depth look at a crucial decade for the Big 3.

This Is Us airs Tuesdays (9 p.m. ET) on NBC.