When news broke that popular YouTube vlogger Calen Bratayley had died aged 13 of natural causes, many questions were raised by fans of the family's channel as to why a "seemingly healthy boy" had passed away so young.
On Monday night, Caleb's mother Katie revealed that her son had "passed away from an undetected medical condition".
© Photo: InstagramCaleb Bratayley was a member of the Bratayley clan whose home videos earned them a massive following on YouTube
Posting the news on Instagram, Katie wrote: "Sadly, tests have confirmed today that Caleb passed away from an undetected medical condition.
"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."
The family, whose home videos have earned them 1.3 million subscribers and have been seen more than a billion times, also revealed plans to live stream his memorial, which will take place on Tuesday evening, local time.
"Due to an outpouring of support and people's hope to be part of his memorial, we have decided to live-stream the ceremony tomorrow at 8pm EDT. Additional information below. Thank you for all your kindness during this difficult time."
Caleb's mother announced the news of his death on Monday and revealed it had come as a "shock" to them.
Referring to her son by his nickname of "baked potato", she said the family would miss the "incredibly funny, loving and wonderful spirit (that) made us all fall in love with him as a YouTuber, friend, brother and son".
In a video made the day before he passed away but posted afterwards, the youngster is seen joking around with his sisters Annie, ten, and Hayley, seven.
A message on the screen said: "It is with our deepest sorrow to report that the Instagram announcement was indeed true.
"In addition to our desire to give the Internet community the chance to begin the grieving process, we also wanted to post this video to show a healthy and happy Caleb doing what he loved.
"Thank you for all the love and support that everyone has shown our family. And we ask for continued love and support as we move through the grieving process."
