What Fueled Lisa Rinna's 'Real Housewives of Beverly Hills' Blow-Up?

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Last night on The Real Housewives of Beverly Hills Lisa Rinna threw water on former child star Kim Richards after Kim threatened to reveal a secret about Lisa's husband Harry Hamlin. ET is with Kim's sister Kyle, who weighed in on the incident.

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"I was in complete and utter shock as we all were," Kyle tells ET. "It was really shocking. She first lunged across the table and everybody was taken aback and she stopped herself. And then she just lost it. She completely lost it."

Lisa's fit of rage was uncharacteristic of the actress, but Kyle says that her reaction was real.

"This was 100 percent a natural reaction that Lisa had," Kyle said. "Our show is not scripted. It's not lightly scripted. That was just Lisa's genuine reaction."

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Lisa later defended her actions in a blog posted to Bravotv.com.

"I am fiercely protective of my marriage and my family, and I'll be damned if I let someone as disturbed as she create false rumors about my husband," Lisa wrote. "I think it's plain to see that Kim crossed the line. That was my 'DO NOT F--- WITH ME' moment. You have just met my inner gangster! I'm just glad that I didn't strangle her on the spot, mainly because I hear the food in jail sucks and orange is not my best color! The crazy part is Kim has met HH once. One time.

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"Look, I own the fact that I allowed myself to be provoked, and it was uncool to break a glass in the restaurant," Lisa continued. "It was not one of my finest moments, but there's only so much my inner gangster can take before she goes postal. It was all very draining, and by the time we got to our conversation the next morning, I was really over it and not looking for another fight."

Of course this isn't the first outburst to occur on reality TV. Porsha Williams attacked Kenya Moore on last year's The Real Housewives of Atlanta reunion show, and on Sunday's episode Phaedra Parks almost struck Kenya with her purse. And who could forget Teresa Giudice's infamous table flip on The Real Housewives of New Jersey or Aviva Drescher tossing her prosthetic leg across the dinner table on The Real Housewives of New York.

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Kyle explained why reality TV cameras can make a usually docile person lash out.

"It is a different dynamic when there's a camera there because the whole world is watching, it seems," Kyle said.

Lisa texted ET's Nancy O'Dell saying that she was also shocked by her outburst and explained that her reaction just goes to show how protective she is of her family.

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