EXCLUSIVE The “Roseanne” reboot is under way, with new characters being added– the children of Darlene (Sarah Gilbert) and David (Johnny Galecki).

I’m told they will have two kids– a son and a daughter. The daughter, named Harris, is supposed to be 14 or 15 years old and aspirational and upwardly mobile– she’s determined to do better than her parents but she’s not snotty about it, says a source. “She has a big heart.”

More controversial will be a casting call for Darlene and David’s son, named Mark, who will be named for daughter Becky’s late husband. In real life, the actor who played Mark–daughter Becky’s boyfriend, then husband– on the original show, Glenn Quinn, died in 2002 from an opioid overdose.

But there’s a twist. The new 9 year old Mark will be “gender creative.” According to my spies, the casting call asks for a kid who can play “sensitive and effeminate” and “displays qualities of both young female and male traits.”

This would be a first for network TV as the “Roseanne” reboot is on ABC and not cable– Showtime or HBO. “Roseanne” was known for its groundbreaking material when it originally aired, notably a lesbian kiss between Roseanne and Mariel Hemingway. There was a huge uproar at the time, but that episode– like all “controversial” episodes of TV shows– airs in syndication without a peep of protest.

A gender fluid child, however, will likely get a lot of attention– for its bravery in telling what seems like a more common story in recent years and from the usual detractors. The “Roseanne” reboot is obviously out to give a jolt to what is a fairly snoozy sitcom world.

Mark would not be TV’s first gender fluid person, however. That distinction goes to actor Asia Kate Dillon, playing Taylor on Showtime’s “Billions.” I’m actually still completely perplexed how “Billions” was ignored by the Emmys, Dillon especially. But that’s for another day.