YouTube star Keenan Cahill has passed away.

According to TMZ, Cahill's manager, David Graham, confirmed his death, citing complications from recent heart surgery.

Keenan had open heart surgery on Dec. 15 but there were complications from the procedure and he was put on life support.

Keenan reportedly passed away Thursday afternoon (Dec. 29) after he was taken off life support in a Chicago hospital.

Long before TikTok, a popular app for overdubs and music overlays, Cahill built up a massive following on social media for his lip-sync videos. TMZ credits him with being one of "the first YouTube influencers to rack up over 500 million views on his channel."

His popularity skyrocketed when rapper 50 Cent made a surprise appearance in one of his lip-sync videos.

After their surprise collab, other artists and celebrities began working with Keenan. A few notable names include Justin Bieber, Katy Perry, Britney Spears, Jason Derulo, LMFAO, and more.

2011 American Music Awards - Show
Photo by Kevork Djansezian/Getty Images

Up until just a few weeks ago, Cahill was still posting videos to his social media accounts.

The YouTube star was diagnosed with a rare genetic disorder called Maroteaux-Lamy syndrome.

Maroteaux–Lamy syndrome, is a progressive condition that causes organs and tissues to enlarge, become scarred or inflamed.

Heart issues are common with some people who have Maroteaux-Lamy syndrome and based on what we know that seems to be related to what happened here.

Our deepest condolences go out to his friends, fans, and loved ones.

Cahill was 27.

Keenan Cahill & Ciara Perform In Honor Of National Teen Pregnancy Awareness Month
Photo by Jason Kempin/Getty Images

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