Kim Richards Threatens To Quit 'Real Housewives Of Beverly Hills' Because Sister Kyle Is Being Bullied

Don't mess with Paris Hilton's aunts!

Real Housewives of Beverly Hills star Kim Richards has threatened to quit the hit Bravo television show because of concerns that sister, Kyle, is being bullied by co-stars Brandi Glanville, Lisa Vanderpump and Yolanda Foster, RadarOnline.com has exclusively learned.

After being confronted about allegations that Kyle's husband, Mauricio Umansky, was cheating on her, "the mean girls, headed up by Lisa, she had a very emotional visit with Kim. Kim and Kyle have had their issues over the years, but when the chips are down, they look out for each other. After Kyle told producers she wanted off the reality show, Kim issued the same ultimatum," a source told Radar.

"Kim has come a long way in her sobriety, and isn't afraid to assert herself now. She demanded that the bullying Kyle was being subjected to stop, or else. Kim only did the show because Kyle wanted her to, and she needs the money. It's not worth it to her though, to see her family getting raked through the coals for ratings."

The latest drama unfolded when the ladies blindsided Kyle during filming last week with allegations that her husband was cheating on her.

Although hunky Mauricio has previously denied being a womanizer, Lisa and Brandi decided “to confront Kyle about it on camera,” an insider previously told Radar. “They absolutely blindsided her, and were relentless.

“Brandi maintained she had solid information to prove that Mauricio has been cheating on Kyle. Kyle became extremely upset, and refused to listen to the girls. She felt especially betrayed by Lisa because they had once been so close.”

The Richards sisters "are contractually obligated to film this season. Kim doesn't want Kyle to end up like Adrienne Maloof and how she was maligned on the show last season. Don't mess with Kim, she isn't the pushover she used to be," the insider revealed.