“This is Us” has been compared to the former NBC drama “Parenthood” so many times, it’s hard to not to expect each episode to end on a warm-hearted note. Though not on the same scale as the premiere, every week the series like to drop a last-minute bomb, and not all of them are happy surprises.

On Tuesday’s (Nov. 29) episode, “The Trip,” all three siblings are finally together in the same room — very exciting, since such an occasion is something we have only seen so far in flashbacks. However, the Thanksgiving reunion quickly turns sour after Randall (Sterling K. Brown) discovers his mother’s (Mandy Moore) letters in his biological father’s (Ron Cephas Jones) drawer.

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The anger, the hurt, the confusion all burst out, as the usually cool, calm and collected Randall seriously spirals. And it’s completely understandable. While this show is not “Parenthood,” it’s also not “Timeless” — no one is traveling through time in order to change the past — and it is beyond infuriating for Randall. Discovering his mother has kept the truth about his biological father a secret from everyone his entire life is a game-changing moment for the Pearsons. Nothing will ever be the same from here on out.

Randall, who openly admits he was favored by his mother growing up, and savored their special bond even though he knew it made his siblings jealous, was something he never wanted to let go of, even well into adulthood. But now the extra attention, something Randall knew he received partially because he was the adopted child, takes on a whole new meaning. He now sees that extra TLC stemming from a place of insecurity, selfishness, and guilt.

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This definitely doesn’t put Rebecca in a pleasant light — but as a mother, it’s what she felt she needed to do at the time to protect her baby. Not that that makes it the right thing to do. Not even close. But that’s what makes “This is Us” so refreshing. These characters are flawed. And they grapple with some serious issues. Even though they appear to be one big happy family from afar, the Pearsons are quite the train wreck.

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While we don’t know how or when, Jack (Milo Ventimiglia) has since passed away. Whether it was before Jack died or not, we also still don’t know, but Rebecca is currently married to her dead husband’s former business partner (Jon Huertas). Kate’s (Chrissy Metz) total self-absorption with her weight issues sabotages all her relationships. She barely speaks with her mother and it’s already clear how much she regrets kicking Toby (Chris Sullivan), the best person to ever come into her life, to the curb.

kate gif This is Us secret is a game changer: Say goodbye to good old Randall

Kevin (Justin Hartley) is a good-hearted guy, but like his twin sister, is abnormally and dysfunctionally self-centered. And now, here’s Randall, who after years of being perpetually on his best behavior in fear that his adoptive family could at the flip of a switch abandon him like his biological parents, is ready to rebel.

young randall and jack gif This is Us secret is a game changer: Say goodbye to good old Randall

Randal knew how lucky he was to be taken in by such caring parents, and grew up with a plastered on smile for every minute of every day. Even though Jack and Rebecca did everything they could to show Randall as much love as possible throughout his life, he never felt truly safe that he could ever act out and not be disowned. Discovering his mother’s betrayal have turned the tables. In Randall’s mind, it’s now them who’s lucky that he’s sticking around.

And for now, we think he’s probably right.

“This is Us” airs on Tuesday nights at 10 p.m. ET/PT on NBC.

Posted by:Emily Bicks

Freelance writer in LA. Sometimes, I'm on camera. And sometimes I'm not. Twitter: @missbicks