LOS ANGELES (AP) — Michael Reagan, the eldest son of President Ronald Reagan and a conservative commentator, has died. He was 80.

The Ronald Reagan Presidential Foundation and Institute announced his death in a post on the social platform X on Tuesday, calling him “a steadfast guardian of his father’s legacy.”

“Michael Reagan lived a life shaped by conviction, purpose, and an abiding devotion to President Reagan’s ideals,” the foundation said.

His cause of death was not immediately announced.

Reagan was a contributor to the conservative Newsmax television network and was known for his talk radio program, “The Michael Reagan Show.”