Kim Richards and her sister, Kyle, have had an up-and-down relationship for years, and on Tuesday's Watch What Happens Live, she opened up about their issues.

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After a dramatic fifth season of The Real Housewives of Beverly Hills, Kim and Kyle were estranged, but after Kim suffered a relapse and later addressed her addiction issues in rehab, she and Kyle were able to make amends.

"It was hard. It was very difficult," Kim explained to Cohen, according to a report by Us Weekly on Wednesday. "For myself, I have to take the hurt — the hurt won't ever really go away. But there's certain things that she had done towards me that I personally have to, things that happened between us, that I have to put aside if I want to move forward."

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Among the two women's hurtful moments were issues involving Brandi Glanville, who speaks openly about her hatred for Kyle, and Kim's dog attack on Kyle's daughter Alexia Umansky, which Kim claimed was nothing more than a nip, but Kyle said nearly took her daughter's hand.

"I couldn't return her phone calls for a while," Kim continued. "She called and reached out to me and I just wasn't ready."

To see more of Kim Richards, be sure to tune into The Real Housewives of Beverly Hills season six, airing on Tuesdays at 9 p.m. on Bravo, and check out a clip from her Watch What Happens Live apperance below.