William is never far from Mulder and Scully's minds, and nothing proved that more than The X-Files "Founders Mutation."

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It's been well over a decade since Scully (Gillian Anderson) put her son up for adoption, and the what-ifs and never-weres continued to haunt the FBI agents as the revival began.

"It's a big part of the emotional arcs for these characters," series creator Chris Carter told TV Insider. "We learn how they feel in ways we haven't seen before. What's interesting is the passage of time, their feelings have changed; they've grown and deepened."

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For those dying for more info about William, you will be happy to know that the Scully's apparent immaculate conception will be addressed during episode 4. Titled "Home Again," the hour will see the agent suffer "a personal tragedy."

I think it was too raw to play these beats [in the original run]," Carter said. "Now, with the passage of time, they ache. But it's funny, both ['Home Again' writer] Glen [Morgan] and ['Founders Mutation' writer] Jim [Wong] seized on this as a story they wanted to incorporate into their larger stories."

Are you ready to learn more about William? Catch The X-Files Mondays at 8 p.m. ET on Fox.

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