Fear the Walking Dead season 7’s Sarah-centric episode explained a mystery that’s been around since she joined the show in season 4. Sarah (Mo Collins) and Wendell (Daryl Mitchell) have been members of Morgan’s group for several seasons now, but have mostly felt like tertiary characters (particularly in the case of Wendell). Despite the significant amount of time that’s passed since they first crossed paths with Morgan (Lennie James) and the others, their backstories hadn’t been explored prior to season 7.

Wendell, who was missing for all but one episode of season 6, still hasn’t returned to the fold, but finally became relevant again in a story that shined the spotlight on Sarah. Fear the Walking Dead season 7, episode 4, titled “Breathe With Me” saw Sarah team up with Josiah LaRoux (Demetrius Grosse) on a search to find Wendell. While the characters did learn his apparent whereabouts, they never did manage a reunion between the brother-and-sister duo, on account of Strand’s warning that he wouldn’t allow Wendell to re-enter the complex. However, their journey did shed some light on their history and the deep connection they share.

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According to Sarah, she has a medical condition that has negatively affected her breathing ever since birth. She said in the episode that when she was a newborn in the hospital, she was placed alongside baby Wendell. By following along with his breathing, she was able to survive her breathing issues. This explains a question that harkens back to their season 4 debut. Since they first appeared in Fear the Walking Dead, Sarah and Wendell have said they were “twins”, but this connection has never been elaborated on. For obvious reasons, the idea of the two being twins has never been taken seriously. It’s always been clear that for the two to count themselves as siblings, one (or both) had to be adopted. Now, Fear the Walking Dead has cleared up this mystery by explaining their backstory.

Wendell from Fear the Walking Dead peering out from inside a truck

Sarah and Wendell aren’t twins, but why they call each other that makes sense now. They may not share the same biological parents, but they have been together since they were both born at the hospital. Having that relationship and being born on the same day seems to be what resulted in Sarah’s view of Wendell as her “twin”.

Fear the Walking Dead season 7 finally exploring their backstory allowed the series to delve into why Wendell means so much to Sarah. The reveal about the role that Wendell played in her early life and how his absence has impacted her (both medically and emotionally) greatly added to the weight of her decision at the end of season 7, episode 4. Knowing that Wendell is better off with Victor Strand (Colman Domingo) than he is with Morgan’s group, Sarah gave up her shot at seeing him again. Assuming that Strand wasn't lying about where Wendell is, then his own perspective on his relationship with Sarah, as well his his efforts to reunite with his "twin sister," can be explored in future episodes of Fear the Walking Dead set within Strand’s empire.

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Fear the Walking Dead releases new episodes Sundays on AMC.