The heart disease can go undetected and people suffering from hypertrophic cardiomyopathy "have few, if any, symptoms,"


As fans continue to mourn the sudden death of 13-year-old YouTube star Caleb Logan Bratayley, new information has come to light about his family’s history of heart disease.

The popular web star died from what his parents say was an “undetected medical condition.” On Tuesday, they told ABC News that the family has a history of “hypertrophic cardiomyopathy.”

The disease causes the heart muscle to become abnormally thick and makes it harder for the heart to pump blood, according to the Mayo Clinic.

Many people with the disease, which often goes undiagnosed, have few, if any, symptoms and can lead normal lives with no significant problems.

The Bratayleys, who are used to sharing their lives with the public, will be broadcasting their son’s memorial tonight on the family’s .

“Due to an outpouring of support and people’s hope to be part of his memorial, we have decided to live-stream the ceremony,” the family posted on their Instagram account.

And while fans are not being shy about their feelings regarding the family’s decision, a source close to the family tells PEOPLE, “They’re trying to create closure for the fans, most of whom are really young. It is definitely a more intimate relationship that they have with their fans than traditional celebrities have with theirs.”

“They’ve been broadcasting their life for a long time – every day for years. It was just a terrible tragedy. They are really good people,” the source adds.

The exact cause and manner of death of the YouTube star is currently being investigated, Bruce Goldfarb, the public information officer of the state medical examiner’s office in Baltimore, tells PEOPLE.