Whilst the rest of the Keeping Up With The Kardashians clan are happy to share naked selfies and voice their opinions on everything from cosmetic surgery to their sex lives, Kendall is far more private when it comes to sharing personal details.
The model hasn't revealed much about her reaction to Caitlyn's transition - until now.
During a recent interview with Women's Wear Daily, Kendall revealed she knew about her father's secret during childhood, and likened the process to "mourning the loss of someone".
"It would probably be different for someone who didn't have to live it through the media," she explained. "But it's been a ride, for sure. It's an adjustment. It's something you have to get used to. I've known since I was a kid. He never confirmed it to me, but I've known for a very long time."
Kendal said Caitlyn is still "the same person". She added: "My dad says it herself sometimes, it's kind of like mourning the loss of someone, because it is. My dad is my dad, but he's not there physically anymore. But she lets me call her dad - that's the last little piece of dad I've got."
Last week, Caitlyn took to Instagram and shared a snap with Kendall, saying: "So great spending time with @KendallJenner! Love my little girl."
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