Update, 10/6: Caleb Logan died of an "undetected medical condition," according to an Instagram post on the Bratayley family account. Fans who wish to celebrate the young YouTube star, whose real name was Caleb LeBlanc, can watch a live-stream of a memorial service scheduled for 8 p.m. ET tonight. The funeral can be livestreamed on Periscope (@bratayley) and Facebook (Facebook.com/bratayley). The family also added, "We'll have more definitive answers in the coming weeks but ask that you help us celebrate his life instead of focus on his death."

Update: Caleb Logan suffered a "medical emergency" and was pronounced dead at a Maryland hospital. TMZ claims law enforcement sources told them that a 911 call was placed around 7 p.m. on Thursday, October 1, and the coroner will conduct an autopsy to investigate Caleb's cause of death.

Caleb Logan Bratayley, of the popular YouTube vlogging family known as the Bratayleys, died at just 13 years old late last week. His mother Katie announced the news on Friday (October 2).

"[Thursday] at 7:08PM Caleb Logan Bratayley passed away of natural causes," she wrote in an Instagram post. "This has come as a shock to all of us. Words cannot describe how much we will miss him."

"His incredibly funny, loving and wonderful spirit made us all fall in love with him as a YouTuber, friend, brother and son," she went on. "We know you tune in to watch each day and eagerly anticipate new videos, but ask that you bear with us while we deal with this tragedy as a family. Please help us honor our, baked potato."

The family, whose real name isn't Bratayley and who live in an undisclosed state, have over 1.6 million YouTube subscribers and 470k Instagram followers. They amassed fans over several years of frequent video posts featuring Caleb and his sisters, Annie, 10, and Hayley, 7. They are represented by Maker Studios, a Walt Disney-owned digital media company, and Variety reports that Caleb had appeared at Disney's August "unboxing" toy event for Star Wars: The Force Awakens. He also sporadically updated a separate YouTube account dedicated to playing MineCraft.

Caleb's parents, Katie and Billy, shared a bittersweet tribute to Caleb Logan on their YouTube page on Sunday, October 4. As the comments underneath reflect, fans are struggling to come to grips with what many see as a mysterious death from "natural causes," especially given that he appeared healthy in a video posted the day before his death. Their confusion was compounded by the fact that fans only know the clan by a last name thought to be a pseudonym. But Caleb's untimely passing has been confirmed by Maker Studios and some fellow members of the YouTuber community, including Nikki Phillippi.

Watch the tribute to Caleb Logan below, and our condolences go out to the Bratayleys.

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