A portion of Kate’s (Chrissy Metz) past was revealed in This Is Us after she dug up a photo of her and the boyfriend she had shortly after Jack’s (Milo Ventimiglia) death - Marc (Austin Abrams). While the show was cryptic about the extent of his presence in Number Two's life, they clearly implied that it wasn't the ideal relationship. Couple that with a handful of telltale signs, it's possible that her experience with him was what kicked off her weight gain.

Marc met Kate while she was applying for a job at the same music store he was working in. From the get-go, the guy was creepy - even Kevin (Logan Shroyer) commented on that. He essentially stalked Kate by going through her resume to find out her name and came to her house unannounced where he introduced himself as her boyfriend, despite them barely knowing each other. While she had apprehensions, Kate went along because both his brothers had their girlfriends visiting and she didn’t want to be left out.

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Fast forward to the present time on This Is Us, Kate and Rebecca (Mandy Moore) reminisced on that night they took the images shortly after Jack passed away. The Pearson matriarch admitted that she was trying to convince herself that everything in the family was fine during those trying times, she then proceeded to apologize for not noticing "it." While the episode never clarified what she was pertaining to, Kate appeased her mom, replying that she didn't notice "it" as well.

This is clearly the beginning of a brand new This Is Us subplot, but given what we know about Marc, alongside the several clues and insinuations peppered throughout the episode, there's a chance that he wasn't the good boyfriend everyone initially thought he was. Perhaps Marc turned out to be abusive which is something that was effectively set up in the show's latest outing. The fact that he tracked down Kate, went over his head, and introduced himself as her boyfriend was alarming enough, it makes sense why everyone is concerned about her.

Abuse comes in different forms, but whatever it is, it takes a psychological toll on its victim. Before meeting Marc, Kate was seemingly losing a lot of weight, which is emphasized by Hannah Zeile's current physique in recent This Is Us flashbacks. After years of feeling insecure about her physical appearance, Number Two appeared to be well on her way to shedding some extra pounds during her teenage years, so it's a mystery why she wasn't able to keep her progress. One bad relationship may have thrown Kate off her weight-loss journey. This is entirely possible considering that she tends to overeat as a way to cope with stress - an unconscious habit that Toby (Chris Sullivan) pointed out recently. Another possibility is that she didn’t want to be the traditional definition of beautiful by being thin following her break-up with Marc. She intended to gain the weight back, thinking that if she maintains a heavier frame, she won't attract more unwanted interest from men moving forward. In this case, she may have thought that it's a form or protection from another possible bad encounter with a boyfriend.

Kate's body image will continue to be a central element in her story going forward. And with the revelation that Toby has lost a lot of weight, it'll be interesting how this arc will shape up with baby Jack in their lives. Regardless of how it pans out, given how This Is Us likes to interweave different narratives from different eras, this works well with the aforementioned theory.

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