‘RHOBH’ Star Kim Richards’ Secret Child: How She Gained And Lost Custody Of Adorable Toddler

Kim Richards is constantly talking and tweeting about her four grown children: newly engaged Brooke, Kimberly, Whitney & Chad. But RadarOnline.com can reveal that the Real Housewives of Beverly Hills star also had custody of another much younger child five years ago.

In the summer of 2009, Richards was given custody of her family friend Casey Johnson’s 3-year-old daughter, Ava-Monroe, when the desperately troubled Johnson & Johnson heiress, then 29, checked into rehab at Cliffside Malibu, a 2013 book alleges.

“Casey . . . turned Ava over to Kathy Richards’ sister Kim, who had her own long history of alcohol addiction,” Crazy Rich: Power, Scandal, and Tragedy Inside the Johnson & Johnson Dynasty author Jerry Oppenheimer claims in his juicy tell-all.

Johnson’s mother Sale Rashad approved of the arrangement, Oppenheimer explains, because “Kim had been sober for ten years and at that point she was fine.”

Richards infamously relapsed and checked into rehab in December 2011.

The 49-year-old reality star was such a great stand-in mom that Ava began calling her “mommy”— which infuriated the increasingly eratic Johnson.

“Casey went ballistic and said to Kim, ‘Give me my kid back! What do you mean she’s calling you mommy, I’m her mommy!'” Oppenheimer claims.

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Johnson had her friend, British socialite Jasmine Lennard, take Ava from Richards, the book continues.

Sadly, just a few months later in January 2010, Johnson was discovered dead in her West Hollywood home. An autopsy later determined she passed from natural causes and suffered diabetic ketoacidosis. She was 30 years old.

Richards checked out of rehab in 2012 and is still sober. She’s currently filming the upcoming season of her Bravo series.