Ryan Knight, who appeared on MTV's The Real World: New Orleans in 2010 and The Challenge in 2013 died at the age of 29. The network announced on Thursday, "The Real World family has lost another member."
It was the second death of a Challenge cast member in November.
Ryan's girlfriend, Makenzie Jauer, then shared this heartbreaking post on Instagram, calling Ryan her "sweet angel."
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Ryan's reality TV costars also responded to the news of his death on Twitter yesterday.
Recently, Ryan posted a picture with fellow Challenge cast member Diem Brown who passed away on Nov. 14 after battling cancer.
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On Nov. 24, he wrote, "Have the type of life, that when you die no one will dare say, "he left us for a better place."