Kelly Clarkson announced the postponement of the remaining August performances of her Las Vegas residency at The Colosseum at Caesar’s Palace due to her ex-husband Brandon Blackstock's illness. The pop singer and talk show host announced the last-minute change in an Instagram post on August 6,

The family of Kelly Clarkson’s ex-husband, Brandon Blackstock, is beginning to speak out after his tragic death at age 48. Brandon died on Thursday, August 7, after a private, yearslong battle with cancer. His brother, race car driver Shelby Blackstock, 35, was one of the first in the family to publicly address his passing.

Kelly Clarkson's "staying strong" but is "heartbroken" for her kids after ex Brandon Blackstock's death, a source tells PEOPLE. The singer and her late ex-husband share daughter River, 11, and son Remington,