Kyle Richards Credit: Gabriel Olsen/FilmMagic

Always there for her sister. Kyle Richards opened up about the death of Kim Richards' ex-husband, Monty Brinson, in L.A. on Thursday, January 28.

"It's so sad. He’s been sick for so long and my sister Kim has been taking care of him," Kyle, 47, exclusively told Us Weekly at a junket for NBC's Celebrity Apprentice. "He’s her best friend, so it was really sad, very sad." (Kyle, who has had a roller coaster relationship with Kim, is a contestant on season 15 of the reality series.)

"It’s a cloud because she’s been so happy and feeling so good and then she loses her best friend. But she’s strong and she’ll get through this just fine," the Real Housewives of Beverly Hills star added. "She has a very big support system."

As previously reported, Brinson died at the age of 58 from cancer on Sunday, January 24. The exes, parents to daughter Brooke, 29, ended their three-year marriage in 1988. Kim, 58, attended his memorial on Thursday, January 28.

"Yesterday I said goodbye to best the friend I've ever had in my life. Monty was an amazing person with an amazing soul. We shared over 30 years of Love & Happiness and brought a beautiful daughter into world. I am so grateful for all that we shared," Kim captioned a throwback Instagram pic last week. "I know we will be together again one day. I love you Monty my angel in heaven. .and I know that we be together again one day. I will carry you in my heart always my love...until then, may you rest in peace."

RadarOnline previously reported that Kyle skipped Brinson's funeral and memorial. Sources, however, tell Us that the story is a "complete lie."

"Kyle went to the memorial on Thursday and [her husband] Mauricio was invited and went as well. As did all of their kids," the source says. "There was only one event for Monty; the memorial. And he was cremated."

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