'RHOBH' Kim Richards, Kyle Richards Family Feud, Sisters At War After Sobriety Struggle & Pitbull Attack — Will 'Real Housewives Of Beverly Hills' Get Along Soon?

It seems that The Real Housewives of Beverly Hills stars and sisters Kim Richards and Kyle Richards are not on the best terms as of late. The duo have had a rocky start on the series, but it seemed like things between them were on the up-and-up during the last few seasons. However, last night's drama, and a relapse from Kim at Eileen Davidson's poker party, just seemed like the beginning of the downhill spiral that their relationship has taken in the last couple of months.

Click here to read the recap of last night's episode.

According to Radar Online, it seems that Kim was a no-show at her sister's birthday party, which took place last week. While some of the other housewives and friends including Davidson, Faye Resnick and Camille Grammer were all present at the festivities, Kim decided not to go.

"Kim not attending her sister's birthday party was impossible to ignore, especially since some of the other housewives were there," an insider explained to the news site.

It seems that what is causing the major rift between the two is the fact that Kim's pit bull attacked Kyle's daughter almost two months ago.

"Things between Kim and Kyle aren't good," the source explained. "While they have had spats in the past, this time is different because Kyle believes Kim is choosing the dog over family."

However, could it also be Kim relapse on last night's episode of RHOBH that is playing into the fight?

Fellow costar Lisa Rinna opened up in her Bravo TV blog about her interaction with Kim on last night's show.

"She asked to use the bathroom and was acting as if she was high on something, which is why I asked her if she had been drinking or was on drugs when we got into the car," the star explained. "I mean, HELLO! Could that car ride with Kim be any more awkward?"

The situation between the sisters seems like it will just have to be hashed out on this years RHOBH reunion, which will air in the next few months.