The "True Colors" singer took to Instagram to pay tribute to the 22-year-old and voice her concerns over gun control in America.
"I'm shocked and horrified. And angry. How many times are we as a nation going to read a horrific story like this, where someone uses a gun to kill an innocent person, and DO NOTHING. I demand gun control," Kesha wrote alongside a black-and-white photo of her with Grimmie.
"This is sickening. I am so so so sorry for Christina's fans and family. My heart is with you. She was a beautiful spirit and will not be forgotten."
Grimmie passed away last night after being shot following her concert in Orlando, Fla.
Her publicist confirmed the singer's death after releasing the following statement to E! News:
"It is with a heavy heart that we can confirm that Christina has passed and went home to be with the Lord. She was at her show in Orlando and, unfortunately, didn't survive the gun shot wounds. We ask at this time that you respect the privacy of her family and friends in their time of mourning. If you'd like to give back to Christina's family in her memory, please consider donating to the families GoFundMe page in their time of need."
Christina's brother Mark, posted a touching message on his Facebook earlier today, saying, "Christina was more than my sister. She was a partner in life. A superstar. A goofball. Introverted. And a friend to everyone. Genuinely. But above all...she was my baby sister. She loved the Lord and her family and was always there for me and I honestly don't know what I'll do without her."