Snubbed! Kim Richards & Kathy Hilton No-Shows At Kyle's Birthday Dinner

Unhappy birthday! Kyle Richards' feud with sisters Kim Richards and Kathy Hilton nearly ruined her birthday dinner and RadarOnline.com has all the details.

Kyle celebrated her forty-seventh birthday at Craig's in West Hollywood Monday night. Noticeably absent from the gathering were her sisters, Kim Richards and Kathy Hilton.

"Kim was invited to the dinner but Kathy wasn't," an insider explained. "Things continue to be very tense. Kathy didn't even call Kyle to wish her a happy birthday!"

Kim, 51, wished her sister happy birthday on Instagram by posting a sweet childhood pic of the siblings. Hilton, 56, publicly remained silent, however.

"Kyle knew that even if she invited Kathy, she wouldn't go. There continues to be bad blood because Kyle discussed Nicky's wedding on Real Housewives of Beverly Hills," the source said.

"Kathy won't be forgiving Kyle anytime soon," the source continued. "The wedding was the last straw in long simmering tensions. And Kathy's husband, Rick is still furious Kyle's husband Mauricio left the Hiltons' real estate company to go out on his own."

However, the birthday wasn't a total bust. Surrounded by close friends Kris Jenner and Faye Resnick, "Kyle felt incredibly blessed to have these long time friends, whom she considers family, to be at her side on her birthday," the source said. "Faye and Kris have always been there for Kyle, especially during times Kim and Kathy weren't."

Meanwhile, Jenner has "attempted to broker peace between Kathy and Kyle," the source claimed. Indeed, the sisters did exchange pleasantries at her Christmas Eve party.

But any hopes of a reconciliation were squashed soon after when Rick Hilton "falsely said Kyle was leaving RHOBH because of the Nicky wedding drama being broadcast on the show. Kyle felt Rick was trying to intimidate her into leaving the show. Not happening," the source claimed.

"Viewers of RHOBH shouldn't expect Kyle to lash out at either Kim or Kathy on the air," the source said. "She will continue to try to keep the drama under wraps. She has a lot of dirt on Kathy that she could make public, but she chooses not to."

"Kyle will always love her sisters, but she is at a point that she won't put up with their drama anymore," the source concluded. "Kyle has a hot husband, and beautiful daughters. She feels blessed."