Bi-partisan sister act: Democrat Kristina Schake -- new Michelle Obama aide -- and GOP sibling, Kori

Kristina Schake (Denise Crew)

Washington has a new bipartisan sister act: Kristina Schake was announced Monday as Michelle Obama's new communications director. Turns out her big sis is Kori Schake, a conservative military expert who served on the National Security Council for George W. Bush and advised the McCain-Palin campaign.

"She's so fantastic -- they're lucky to get her," Kori, a fellow at the Hoover Institution, told us. "I'm now actually worried the president will get reelected in 2012."

Kristina's new job at the White House is to showcase the first lady's pet projects on childhood obesity and support for military families. (Schake's dad and brother are both vets.) The California native co-founded the political consulting firm Griffin-Schake with Clinton alum Chad Griffin, built Maria Shriver's annual women's conference into the feminist Davos, led the fight against Proposition 8 (California's ban on gay marriage), publicized Al Gore's "Live Earth" concert and headed Rob Reiner's foundation -- to name-drop a little. Schake's focus has been on issues rather than politics, which made her a good match for the East Wing. "What makes her so formidable is that she's both substantively expert and a real political gunslinger," Kori said.

On the personal side: big reader, traveler and art historian. Long divorced, with a serious boyfriend she met in Rome. Now he's moving to D.C. -- and Kori was apartment hunting for them Monday.

Schake starts Dec. 6; she replaces Camille Johnston, who left the White House three months ago for an executive position at Siemens Corp.