Fans can't get enough of Jack's backstory as 'This Is Us' finally introduces his brother

On Tuesday’s This Is Us, fans finally got to meet Jack’s younger brother Nicky. Starting with a moment when Jack seemed to track Nicky down in Vietnam, the episode worked in reverse chronological order, including the moment Nicky’s birthday was chosen in the Vietnam war draft.

Fans loved the Jack-only episode and even learned some things:

As the episode continued to move backward, meeting a younger version of Jack and seeing him as an older brother also had fans talking. One exchange in particular had them reaching for tissue, as Jack tried to make his Nicky feel better about wearing glasses and comparing him to Superman’s alter-ego, Clark Kent.

He’s a tough guy in disguise — that’s you, Nicky,” Jack said. “You’re Clark Kent. You’re CK. Tough guy in disguise.”

Many reactions involved finding out more about Jack’s dad, whom fans have only known to this point to be an abusive alcoholic, and Jack’s grandfather, who was introduced Tuesday. In one scene, grandpa offers a “swig” from his flask to Jack’s dad, who says, “Come on, Dad, you know I don’t drink,” and viewers were in shock.

Pobably the most emotional moment of the night — the one that had people saying things like, “who the hell needs to ugly sob on a Tuesday” — came when Jack and his dad visited baby Nicky.

“Big brothers look out for their little brothers,” Jack’s father said. “That’s all that matters.”

This Is Us airs Tuesdays at 9 p.m. on NBC. Watch clips and full episodes of This Is Us for free on Yahoo View.

Check out what fans had to say about Jack and Rebecca’s first date on This Is Us:

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