We Finally Know What Causes the Kevin & Randall Rift on ‘This Is Us’ and It’s Not What We Expected

*Warning: Spoilers ahead*

In This Is Us season four, episode 15, the Pearsons take positive steps toward getting their lives back. Randall (Sterling K. Brown) starts therapy, Kate (Chrissy Metz) sets boundaries and expectations with Toby (Chris Sullivan) and Kevin (Justin Hartley) returns to Los Angeles to spend time with his beloved mom, Rebecca (Mandy Moore). But, it wouldn’t be This Is Us without some bumps along the way, would it?

First off, Randall and his therapist (played by Pamela Adlon) do not immediately hit it off. When she questions how pivotal his role is in his family and admits that she knows his family history because she’s seen his speeches, he feels exposed and defensive. He storms off after she asks him what would happen if he stopped trying to be the Superman of his family (and rudely criticizes her coffee maker). Ultimately, with a little help from Beth (Susan Kelechi Watson), he realizes that therapy might take some getting used to and he really needs to give it another shot.

Meanwhile, Toby tries to prove to Kate that he can be present with her and baby Jack by refurbishing their garage as a music studio. While she appreciates the gesture, she needs time and space before she can forgive him for checking out of family life since Jack’s birth. Eventually, however, she tells him she’s sick of feeling pitted against him and is ready to move forward. Speaking of rocky roads, Kate also has brunch with Madison (Caitlin Thompson), who’s eager to patch things up after sleeping with Kevin. Afterward, Kate tells Toby it was just a fling…but was it?

Speaking of Kevin, he spends the episode bonding with Rebecca. He takes her to Joni Mitchell’s home, where they reminisce about better days and she basically begs him not to make her go to her doctor’s appointment so she can ignore reality just a little bit longer. Kevin says he doesn’t want to perpetuate his reputation as a screw up in the family but assures her he can continue to be the fun son that she knows and loves. Interestingly enough, that promise to Rebecca is what seems to lead him and Randall into the fight we’ve been theorizing about for months now. Watch the episode 16 teaser and see what we mean.

In season four, episode nine, we learned that Kevin and Randall would have a blow-out fight that would lead to them not speaking. At the time, we assumed that their fight was caused by the fact that Randall hid Rebecca’s heath issues from Kevin, but that’s not the case.

Instead, they start fighting because of classic sibling rivalry. Historically, Randall has been the favorite son who Rebecca can count on and Kevin has been the fun one who gives her a run for her money. Now, Randall is struggling to try and hold his family together despite Rebecca’s diagnosis and his anxiety, but he’s losing his grip. Kevin, meanwhile, has promised Rebecca that he’ll continue to be surprising and spontaneous. As she tells him in episode 15, that’s what she wants right now. She doesn’t want Randall telling her what to do or worrying over her, she wants to create memories while she still has a memory to speak of.

With Randall’s mental health issues and Kevin’s need for love and acceptance, we can’t help but worry about how this all will play out. We’ll have to wait and see what happens when This Is Us season four, episode 16 premieres next Tuesday, March 3, at 9 p.m. PT/ET.

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