Brandon Blackstock was reportedly diagnosed with melanoma, a type of skin cancer, three years ago.
On Thursday, a representative for the Blackstock family announced that the talent manager had passed away "peacefully". He was 48.
The sad news came just hours after Blackstock's ex-wife, Kelly Clarkson, announced she was postponing her Las Vegas residency so she could focus on caring for the former couple's two children: daughter River, 11, and nine-year-old son Remington.
Clarkson has not yet publicly commented on Blackstock's passing.
However, sources told TMZ on Thursday that the Texas native had been battling melanoma for the past three and a half years.
Melanoma is considered the most dangerous form of skin cancer as it can spread to other areas of the body.
A sign may be a new mole or change in an existing mole. The main treatment is surgery.
Blackstock and Clarkson were married from 2013 until their divorce was finalised in 2022.
And a source told People on Thursday that The Kelly Clarkson Show host was "devastated" for her children.
"When she found out that he was sick, she remained protective of him for their sake," the insider told the outlet. "Kelly has always tried to keep things classy. It became clear earlier this year that Brandon was not doing well. She's been devastated for the kids."
The TV producer, the son of producer-manager Narvel Blackstock and former stepson of country music superstar Reba McEntire, was previously wed to Melissa Ashworth between 2001 and 2012.
Blackstock and Ashworth also shared daughter Savannah, 23, and son Seth, 18.