We've already got a big clue as to when Jack (Milo Ventimiglia) will die on This Is Us.

As for when the show's other beloved dad — William (Ron Cephas Jones) — will leave us, things aren't so certain. Will he even make it to Season 2?

"I can't tell you," series creator Dan Fogelman said at the Television Critics Association winter previews in Pasadena, Calif. in early January. Though William's passing is inevitable — we've see a glimpse of son Randall (Sterling K. Brown) in mourning that pretty much confirms his biological dad's demise from cancer — William seems to have a rejuvenated sense of self lately thanks to what Randall's wife Beth (Susan Kelechi Watson) called a "chemo boost" from his refusal of treatments. So, much like Jack, William's death is sadly imminent, but when isn't clear. Despite that though, Fogelman said he's not going away anytime soon.

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"The back half of the season is very much focused on William's fight with cancer," Fogelman said. "Different answers are searched for, and different possible outcomes are on the table. In terms of Randall's storyline and William's storyline, our focus really turns to that."

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We'll learn a lot more about William overall in the rest of this season, including more on his relationship with the woman who gave birth to Randall, and more on William's relationship with his recently discovered male partner Jessie (Denis O'Hare). "There's a little more," Fogelman said. "I would do a ton more but Denis O'Hare is a busy man and schedules aren't flexible."

There's more of Randall too. As This Is Us continues to dig deeper into its web of primary character stories, backstories and the stories of people close to the Pearson clan, it'll play with variations of format. "In a couple of episodes there's an episode with entirely Sterling," he promised, meaning we're going to get to know a lot more about Randall and likely, his awesome wife Beth too.

This Is Us airs Tuesdays at 9/8c on NBC.