Brandon Blackstock, also known as the former stepson of Reba McEntire, has died at 48 from a three-year cancer illness.

“It is with great sadness that we share the news that Brandon Blackstock has passed away,” a family rep told PEOPLE. “Brandon bravely battled cancer for more than three years. He passed away peacefully and was surrounded by family. We thank you for your thoughts and prayers and ask everyone to respect the family’s privacy during this very difficult time.”

On Wednesday, Aug. 6, Kelly Clarkson revealed that Brandon Blackstock had been battling an illness and postponed her Las Vegas residency to be with their children — River, 11, and Remington, 9.

Blackstock also had two older children, Savannah and Seth, from a previous marriage, and became a grandfather in 2022 when Savannah welcomed a son named Lake.

In March 2024, Blackstock was seen at the Houston Rodeo with River, Remington, his brother Shelby, and Shelby’s mother, Reba McEntire. Reba was married to Brandon’s father, Narvel Blackstock, from 1989 to 2015.

Narvel once managed Clarkson, and she first met Brandon at a 2006 ACM Awards rehearsal — while he was still married to his first wife, Melissa Ashworth.

After their wedding, Blackstock — who also managed Blake Shelton — took on the role of Kelly Clarkson’s manager.

Clarkson filed for divorce in 2020, and the split turned contentious. A major point of dispute was their Montana ranch, which Blackstock was living in at the time. Although he fought to stay, Clarkson was ultimately awarded ownership of the property and won the legal battle to have him evicted.

Brandon Blackstock was born on December 16, 1976, in Fort Worth, Texas, to music manager Narvel Blackstock and Elisa Gayle Ritter. He was the stepson of country star Reba McEntire. Following in his father’s footsteps, Brandon became a talent manager and worked with several major country artists, including Blake Shelton and Rascal Flatts. He later managed Kelly Clarkson, whom he met in 2006. The two began dating in 2012, got engaged later that year, and married in October 2013.

Together they had two children, River Rose and Remington Alexander. Brandon also had two children, Savannah and Seth, from a previous marriage. In 2020, Clarkson filed for divorce after nearly seven years of marriage, and their split became highly publicized due to legal battles over property, spousal support, and unpaid commissions. Their divorce was finalized in 2022, with Clarkson receiving primary custody of their children. In 2021, Brandon left the entertainment industry to focus on ranching in Montana and started a company called Valley View Rodeo.