Socialite Tinsley Mortimer has started filming scenes with the ladies of "The Real Housewives of New York City" season 9.

While it seems true that Tinsley is joining the cast of season 9, her role in the reality show remains uncertain.

"Tinsley is now staying with Sonja Morgan at her Upper East Side townhouse. She is filming as Sonja's friend. Sonja is responsible for introducing Tinsley to the rest of the cast," revealed an insider. The same source revealed that Tinsley has been filming for several weeks and shot scenes in the Hamptons last November 5.

Despite her involvement in the upcoming show, it remains unknown whether Tinsley will join the ranks of Morgan, Bethenny Frankel, Ramona Singer, Carole Radziwill, Luann de Lesseps and Dorinda Medley in season 9. Some speculate that she will replace season 8 rookie Jules Wainstein, who was previously reported to leave the hit Bravo show.

Bravo has yet to give an official statement on cast additions for season 9, so fans can only speculate for now.

"Producers will determine if she will officially join the cast in the coming weeks," said the insider.

Previously, Tinsley, a Columbia graduate who broke up with her businessman husband in 2009 after seven years of marriage, opened up at the Harper's Bazaar about her one-season stint on the CW reality series "High Society."

"People already loved to have me, and then my show wasn't successful, so instead of saying, 'Oh well, she tried, it was tarnish, tarnish, tarnish," she said. "I didn't even want to go out anymore. I didn't want to do anymore. I was tired," she added.