During last night's episode of The Real Housewives of Beverly Hills, Kyle Richards' family drama was a hot topic for both herself and her co-stars, namely Lisa Vanderpump.

Report: 'RHOBH' Yolanda Foster Thinks Kyle Richards Is Using Her For Publicity

After revealing she'd been univited, and then reinvited, to the wedding of Nicky Hilton, her sister Kathy's daughter, a feud between her husband, Mauricio Umansky, and Kathy's husband, Rick Hilton, was teased. So, what's really going on between the two men? Brandi Glanville revealed details on Twitter earlier this year.

“[Kyle Richards], your husband use (sic) to work for Kathy’s husband until he secretly stole agents & clients to start the Agency #STFU… Talk about me, call me a liar, which I am not - you will get it back," she wrote at the time, according to a report by Reality Tea.

Kyle Richards On Nicky Hilton's Wedding: Was 'RHOBH' Star Banned Due To Feud With Sister?

In response to Glanville's tweets, Richards reportedly sent her a legal letter, demanding she stop talking about her personal business. However, Glanville has continued to speak of the Richards' family, and those tied to it, in the months since, and a lawsuit has not yet been filed.

While it's hard to say whether or not Umansky and Rick Hilton are truly feuding, it did seem like it last night, when it was noted that Umansky was not invited to Nicky's ceremony.

For more of Kyle Richards and her family, tune into The Real Housewives of Beverly Hills season six, airing on Tuesday nights at 9 p.m. on Bravo.

Tags: kathy hilton rick hilton kyle richards Mauricio Umansky Bravo Reality TV The Real Housewives of Beverly Hills nicky hilton