Actor Gary Sinise's son, McCanna Anthony Sinise, died last month at the age of 33, the actor announced Tuesday.

"Mac" had struggled with Chordoma, a rare form of cancer for years. He underwent a surgery to remove the first tumor in 2018 and a second procedure the following year, though the Chordoma persisted and gradually saw him deteriorate, the actor stated in a tribute to his son.

Mac was first diagnosed after joining the Gary Sinise Foundation. He often played as a drummer in his father's Lt. Dan Band, a musical project named for his father's iconic role as Lt. Dan in the film "Forrest Gump."