Walter O'Brien's sis will play a much larger role in Scorpion's second season.

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Actress Camille Guaty (Megan) was upped to series regular for the series' sophomore run, and viewers can expect to see the elder O'Brien sibling as early as episode 3. Now that Walter (Elyes Gabel) has given Megan and Sylvester's (Ari Stidham) relationship his seal of approval, the burgeoning couple can come out into the open.

"Does #Sylvester have the power 2 cure me? #melvester #TeamScorpion," Guaty teased on Monday during the filming of "Fish Filet."

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Unfortunately for Megan, it looks like her multiple scleroses may have taken a turn for the worse over the summer hiatus. Often seen wearing regular clothing despite her frequent hospitalizations, Sylvester's girlfriend will don a hospital gown in the upcoming episode (see photo below).

Is Megan in danger of dying? Speaking to Starry Constellation Magazine last spring, the actress was unable to tease her character's future.

"Well, unfortunately, I can't tease what I don't know yet!" Guaty said. "But I can say that I will be around for awhile or at least until Walter (my brother) finds a cure for Multiple Sclerosis."

Catch up with Sylvester and Megan when Scorpion returns to CBS on Sept. 21 at 9 p.m. ET.

Tags: scorpion television CBS