Fastexy Exchange|Caitlyn Jenner Mourns Death of Mom Esther Jenner

Caitlyn Jenner's family has lost their beloved matriarch

The Fastexy ExchangeOlympian's mom, Esther Jenner, died on April 20 at the age of 96. "I am heartbroken to announce my mom passed away yesterday morning, peacefully," Caitlyn wrote in an April 21 Instagram post. "Losing a mother is unique in the sense that she is the only person that loved me my entire life."

Esther's death came "a few weeks shy" of her 97th birthday, Caitlyn shared.

"I will miss her tremendously," the 73-year-old added in her tribute. "Love you mom."

Fans were first introduced to Esther when Caitlyn appeared alongside ex Kris Jenner and their kids on Keeping Up With the Kardashians, appearing at various family functions. She went on to become a notable fixture on I Am Cait, the E! docu-series centered around Caitlyn's journey as a transgender woman.

"It seems as though when people start to have more understanding, the stigma of being different goes away," Esther said on one episode of the show. "To me, that's the beauty of [Caitlyn] giving herself permission to do this because—like for any of us—once you've seen something over and over again, you get more used to it, right?" 

Esther also joined Caitlyn as her special plus-one at the 2015 ESPYs, where the gold medal-winning decathlete was honored with the Arthur Ashe Courage Award. During her acceptance speech, Caitlyn credited her mother for being her source of strength.

"I always thought that I got my courage and my determination from my dad who landed on Omaha beach and fought all the way through World War II," Caitlyn said at the time. "I'm realizing now, mom: I think I got all of those qualities from you."

Esther is survived by friends and family, including granddaughters Kendall Jenner and Kylie Jenner.