According to a report from People magazine on Thursday, April 7, the 31-year-old reality star is apparently still upset about Robs relationship with Chyna.

A source tells the mag that Khloe felt betrayed ever since finding out that Rob was dating Tyga's baby mama. "This feeling has never changed. After finding out about the engagement, she is furious at the lack of respect," the source said.

Rob proposed to Chyna on Monday, April 5 to much fanfare on social media and the family is said to be blindsided by the news. Several members of the Kardashian-Jenner clan were enjoying a ski trip in Vail, Colorado as they jetted out the same night that the happy couple shared their engagement news.

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"She can't believe Rob didn't tell the family in advance. She thinks Rob is causing drama on purpose and wants them [his family] to be arguing," the source explained. "Khloe plans on ignoring the news. She is not going to send Rob any well wishes. She is not happy about the engagement, and is not going to pretend that she is."

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Khloe was the sibling who took a formerly reclusive Rob under her wing when he battled diabetes and cut himself out of the 'Keeping Up With The Kardashians' family business, blocking himself off from most social contact.