Why Toby & Kate Might Divorce On 'This Is Us' Season 4

Ron Batzdorff/NBC

Kate and Toby have weathered a lot on This Is Us, but since that Season 3 flash-forward when Toby wasn't wearing a ring and Kate was nowhere to be found, there's been plenty of fan speculation that Toby and Kate get divorced on This Is Us. Of course, there's no telling when (as much as we'd love the show's creators to tell us), but recent developments in Season 4 might hint that the end of Katoby is nigh.

Kate and Toby met while they were trying to lose weight together, and a lot of their relationship has revolved around their weight. Now, after the news that their premature son, Jack, was born blind, Kate is eating to cope with her feelings, and Toby is heading to the gym (in secret) to work out the pain and thoughts he has about their baby and the new challenges their little family will face. That means that... Toby is shredded now and Kate is gaining the weight she lost back.

In the Oct. 8 episode of This Is Us, "Unhinged," Kate shed a few tears over Toby's transformation and there's a good chance these tears could grow into something more — like resent, disdain, and eventually, a divorce for this This Is Us couple.

Writer and producer Isaac Aptaker told Entertainment Weekly that Toby's fitness outlet is the only way he knows how to take all this information in right now. "He’s faced with this massive curve ball finding out his son is blind, and he’s found an outlet for himself for all that anxiety, for all of that pain, and that is at the CrossFit gym," Aptaker said.

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And all of this is fine, because it's a healthy way for Toby to process, but Kate broke up with Toby in Season 1 of This Is Us because she thought that he was sabotaging her own weight-loss journey. Now, Toby is focused on fitness and Kate is not. Kate's own weight is not top of mind for her right now, given that she has to care for baby Jack, and, as Aptaker says, it's not so much that Toby is losing weight that he's keeping it a secret behind his wife's back.

Raising a newborn is stressful in and of itself, but raising a blind child is a different ball game than what Toby and Kate had prepared for. This new stress, coupled with Toby and Kate keeping secrets, could drive the couple apart. Kate could be mad that Toby is able to change himself in a way that Kate can't at the moment, and Toby could be angry that she doesn't understand that he's doing his CrossFit as much for her and Jack as he is for himself.

Then, Splitsville, population of two.

Ron Batzdorff/NBC

In an interview with Entertainment Weekly, Chris Sullivan, who plays Toby, played coy about the future of Toby and Kate. “Baby Jack presents challenges in the relationship just as any new baby, new parents are trying to figure it out," he said. "They’re trying to navigate all kinds of new things. Obviously, the ghost of Jack is in the room now via the name for the rest of the series, and that will bring stuff up for Kate.”

This Is Us is always setting up fans for further heartbreak, but this time, it's Kate and Toby who may be headed for the worst heartbreak of them all.