What happened to Gary Sinise’s son?

Gary Sinise and his family are reeling from the loss of the Oscar-nominated actor’s beloved son, McCanna “Mac” Sinise. A fixture on both the big and small screens for the past 30 years, Sinise has nonetheless put his career on the back burner for the past few years as his family has been dealing with his son’s illness.

Appearing in numerous hit movies across the 1990s, including Of Mice and Men, Apollo 13, and Forrest Gump (which earned him an Academy Award nomination), Sinise reinvented himself as a TV leading man in the 2000s, starring as Det. Mac Taylor (a character who shares a name with Sinise’s son) in all nine seasons of CSI: NY from 2004-2013. More recently, he led the short-lived spinoff Criminal Minds: Beyond Borders and had a regular role in the fourth season of Netflix’s 13 Reasons Why.

Sinise has not had an acting credit since 2020, however, and for a very understandable and tragic reason.

What illness did Gary Sinise’s son have?

On Feb. 27, 2024, it was announced that McCanna “Mac” Sinise (born Nov. 10, 1990) had passed away on Jan. 5, 2024. The news came six years after Mac’s diagnosis with chordoma, a rare form of bone cancer that affects the spine, in 2018. Like his father, Mac had gone into the arts and was a talented musician — before his death, he had completed work on a second album, movingly titled Resurrection & Revival. In addition, Mac had worked for his father’s charity, the Gary Sinise Foundation, since 2017.

Chordoma is a particularly difficult type of cancer to treat as it is tricky to remove via surgery or radiation and there is currently no approved form of chemotherapy for it. In September 2018, Mac had spinal surgery to remove the initial tumor. However, in May 2019, a scan revealed that the cancer had spread, necessitating another surgery. Despite his declining health and increasing disability, Mac continued with his duties at his father’s foundation, until his third and final spinal surgery in November 2019.

“The story of Mac Sinise’s journey with the Gary Sinise Foundation is one of courage, resilience, and the enduring power of family,” read the charity’s obituary for Sinise’s son. “As the foundation continues its mission to serve those who protect and defend, Mac’s impact remains woven into its fabric. His love for music, dedication to the cause, and unwavering spirit have left an indelible mark, reminding us all of the strength found in unity, purpose, and the relentless pursuit of service to others.”

In a tribute to his son, Sinise — a devout Catholic himself — stressed that his son’s faith carried him through his illness. “Mac was a man who loved his Catholic faith, and there is no doubt that his strong faith sustained him through the awful 5 ½ year battle with this crippling Chordoma cancer,” he said, before sharing Mac’s favorite quote from St. Augustine. “You have made us for yourself oh Lord, and our hearts are restless until they rest in you.”