Denise Richards says daughter Sam, 5, learned her father Charlie Sheen was spending Christmas behind bars from a classmate in her kindergarten class.
"It's sad. It's a sad situation," Richards, 38, said in an appearance on The Oprah Winfrey Show Tuesday. "Their dad was in jail on Christmas."
Sheen was arrested in Colorado Christmas morning on felony second degree assault charges for allegedly threatening his wife Brooke Mueller.
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Eventually "I did have to tell them about their dad," continued Richards, who split from Sheen in 2006 after four years of marriage. They are also parents to daughter Lola, 4.
During their marriage, Richards said that Sheen had "a very sharp tongue, he played on my insecurities."
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Even though she admits it was a verbally abusive relationship (which Sheen has denied), Richards said "he never hit me."
Richards was about five months pregnant with Lola when she filed for divorce.
"I was terrified and relieved that I had the courage to do it," the actress said. "Our daughters didn't ask to be born into our conflict....It was impossible to make [our marriage] work."
Now, she is cordial with her ex.
"Charlie and I are in a good place now... It's taken a lot of work on our part," she said.