02/22/2013 08:59 pm ET

Stephanie March To Visit 'Happy Endings' As Alex And Jane's Sister And More Casting News

A-mah-zing news, "Happy Endings" fans -- the show has finally cast Alex and Jane's long-rumored (but elusive) older sister, and it sounds like she'll be Serb-ing her siblings a whole new lesson in the Kerkovich Way.

According to TVLine, "SVU" alum Stephanie March will play Brooke, and her arrival in a spring episode will "shift the Kerkovich family dynamics in a major way, mostly because Brooke can out-Jane Jane."

The only part that sooks is that "Happy Endings" has been displaced from the ABC schedule until March 29, when it will make its controversial Friday debut.

In other casting news ...

"CSI: NY" star defects to "Covert Affairs." Hill Harper will join the USA spy series as a regular in Season 4. His character is described as "ambitious, intelligent and slightly cocky," and he'll be looking to make the transition from the CIA's Latin America station back to Washington -- and turning to Annie and Auggie to help him accomplish that goal. But can he be trusted? [The Hollywood Reporter]

Steven Weber will visit "Dallas." He'll recur as Governor McConaughey, "an ambitious politico who conspires with Cliff Barnes and Harris Rylan" to bring down the Ewings. [TVLine]

"All My Children" welcomes former stars. Julia Barr will reprise her role as Brooke English, while Eden Riegel will have a return cameo arc as Bianca Montgomery in the online revival of the soap. [TV Guide and Deadline]

'Happy Endings' Season 3