Gary Sinise Reveals 33-Year-Old Son Mac Died After Rare Cancer Battle: ‘We Are Heartbroken’

Gary Sinise's son McCanna “Mac” Sinise died after battling a rare form of cancer for five-and-a-half years. He was 33.

“Like any family experiencing such a loss, we are heartbroken and have been managing as best we can,” Gary, 68, wrote in a tribute when announcing his son’s death on Tuesday, February 27. (Mac died on January 24.)

Gary continued: “As parents, it is so difficult losing a child. My heart goes out to all who have suffered a similar loss, and to anyone who has lost a loved one. We've all experienced it in some way.”

Gary, who is known for his role as Lieutenant Dan Taylor in Forrest Gump and Detective Mac Taylor in CSI: NY, detailed his son’s battle with Chordoma after being diagnosed in August 2018. (Chordoma is “a rare type of bone cancer that happens most often in the bones of the spine or the skull,” according to the Mayo Clinic.)

‘Forrest Gump’ Cast: Where Are They Now? Tom Hanks, Sally Field and More

“While our hearts ache at missing him, we are comforted in knowing that Mac is no longer struggling, and inspired and moved by how he managed it. He fought an uphill battle against a cancer that has no cure, but he never quit trying,” Gary’s tribute continued, noting that he and wife Moira Harris — who was diagnosed with breast cancer in June 2018 but has since gone into remission — had likened Mac to the soldier in 1917 who “keeps getting back up, refusing to quit and keeps running forward.”

Sinise initially revealed Mac’s cancer battle during a December 2023 interview. That same month, he and Harris, 69, brought their son to the emergency room.

“He was having trouble getting his breath and after stabilizing him, he was admitted. I stayed with him as I had done many times before. During the first few days, I thought this would be another trip where we get things under control and head home,” Gary wrote. “But the days got tougher, and on January 5th, with the family all around him, he let go. His battle with Chordoma was over and he was at peace.”

The CSI: NY star also detailed Mac’s accomplishments. His late son held the Assistant Manager of Education & Outreach position at the Gary Sinise Foundation from February 2017 to 2020, when he stepped away from the job due to his cancer battle. Mac graduated from the University of Southern California where he studied songwriting and composition at the Thornton School of Music. His album Mac Sinise: Resurrection and Revival will be released posthumously.

Celebrity Deaths of 2024: Stars We Lost This Year

“I am so blessed, fortunate, and proud to be his dad,” Gary wrote, noting that he and Harris wanted to share Mac’s story to “shine a little bit of light on what has been a difficult time."

Mac is survived by his parents, Gary and Harris, along with his sisters, Sophie and Ella, along with their children.

“We were blessed to have you in our lives as son, brother, and friend,” Gary concluded. “And we will miss you and love you for eternity.”