Kim Richards Credit: Gregg DeGuire/WireImage

He will be missed. Kim Richards' ex-husband Monty Brinson died on Sunday, January 24, at the age of 58 after a long battle with cancer.

His former brother-in-law Rick Hilton, who is married to Richards' half sister Kathy, announced the news on Instagram Sunday night, writing, "We have lost Monty Brinson after a brave battle with cancer. His heart was a big as the moon and he was loved by all he Met. He will be sorely missed. I love You always!"

Richards, 51, and Brinson, who were married for three years and had a daughter, Brooke, divorced in 1988 but remained close, and even lived together recently as Brinson's health deteriorated.

Brinson, an heir to a supermarket franchise, was a staunch supporter of the troubled Real Housewives of Beverly Hills star, and defended Richards last year after she was arrested twice and spent time in rehab.

“One day the people that didn't believe in you will tell everyone how they met you. That quote is in honor of @kimrichards11,” Brinson captioned a throwback picture with Richards on Instagram in August. “All I will say at this time besides being best friends, and personally a person who has a great heart is thankful to all her fans and friends for believing in her. Personally I have not seen her but we speak everyday. Do I know everything absolutely. Do I take up for my family and friends absolutely. Do I say it like it is. Absolutely.”

One day the people that didn't believe in you will tell everyone how they met you. That quote is in honor of @kimrichards11 all I will say at this time besides being best friends, and personally a person who has a great heart is thankful to all her fans and friends for believing in her. Personally I have not seen her but we speak everyday. Do I know everything absolutely. Do I take up for my family and friends absolutely. Do I say it like it is. Absolutely. Is my heart filled with love for everyone absolutely. Without going into detail 90 per-cent of what you read is completely false. But for her fans that have stayed with her through this roller coaster will see her very soon at what she's done best all her life since the age of 4. I'm excited for her. And personally I would like to thank everyone who stood by her through this rough time. Remember everyone in life goes through a rough time one way or another. I always say know the facts before being judgmental #life #love #heart #thankful #blessed #rhobh #friends #family #heart

A photo posted by Monty Brinson (@montybrinson) on

Richards was equally supportive of Brinson, taking to Twitter on Friday, January 22, just days before he died, to thank fans "for all the love and prayers for Monty!"

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