The pop star dedicated her performance of the ballad "Warrior" to the Olympic gold medalist during her show at the Vector Arena.
(At this time, Bruce Jenner has not chosen to publicly identify as a woman and so E! News will continue to refer to him as Bruce and use male pronouns, until he indicates otherwise.)
Lovato admitted to the audience that she didn't know who Jenner was until Keeping Up With the Kardashians.
"Let's be honest, neither did you," she said to the crowd. "But I just want to dedicate this song…It's so cheesy that I'm even doing this, but whatever. I want to dedicate it to someone who became an even bigger hero last night—Bruce Jenner!
"By the way, never ever thought I'd dedicate a song to him but he was honest and he was open with his story," Lovato continued. "No matter if you agree with it or not, he probably saved so many lives and educated so many people [about] transitioning into becoming a woman and being transgender and what that's all about. So, yeah, I just want to dedicate it to Bruce Jenner."
The opening lyrics of the beautiful ballad? "This is a story that I have never told. I gotta get this off my chest to let it go."
She goes onto sing, "Now, I'm a warrior. I got thicker skin. I'm a warrior. I'm stronger than I've ever been."
The father of six and step dad of four said during his interview with Diane Sawyer on Friday that he began struggling with his gender identity when he was a little boy.
''Yes, for all intents and purposes I am a woman," Jenner said. "People look at me differently. They see you as this 'macho male,' but my heart and my soul and everything I do in life, it is part of me, that female side is part of me. It's who I am. I was not genetically born that way."
At the time, Lovato said Kim was a like a "big sister" to her.
"I feel like there are some people that you're friends with that talk to you on Twitter or you text, but the people that are really there for me are the people that were there for me when I went into treatment," Lovato told Billboard in September 2011. "The people that were calling me while I was in there were Kim Kardashian and Selena Gomez. Those two girls, they meant the world to me. They still do."
Learn more about what it means to be transgender at http://glaad.org/transgender
If you are transgender and need help or advice, contact the Trevor Project http://t.co/guMjyYIfng