In a poignant and deeply personal announcement, Gary Sinise—the acclaimed actor celebrated for his iconic role as Lieutenant Dan in Forrest Gump and his tireless advocacy for veterans—shared the news that his son, McCanna Anthony “Mac” Sinise, has passed away at the age of 33. The revelation, shared through the Gary Sinise Foundation and social media, has touched the hearts of millions, highlighting a five-and-a-half-year battle with an exceptionally rare and incurable disease. Mac’s journey was one defined not by the tragedy of his diagnosis, but by the extraordinary resilience and creative spirit he maintained until his final moments.

The Sinise family’s struggle began in the summer of 2018, a period that brought a staggering double blow to their household. On August 8, 2018, Mac was diagnosed with Chordoma, an ultra-rare form of bone cancer that affects only about one in a million people annually.¹ This devastating news arrived just three months after Mac’s mother, Moira, had been diagnosed with stage three breast cancer. While Moira’s treatment eventually proved successful and she entered remission, Mac’s condition followed a much more grueling and relentless path. Chordoma is notoriously difficult to treat, often originating in the spine or the base of the skull, and it began a progressive assault on Mac’s nervous system.²+1

Gary Sinise’s tribute to his son was raw and reflective of a father’s profound grief.³ He noted that while his family had spent decades supporting the families of “fallen heroes” through his foundation, the experience of losing his own child brought a new, searing level of heartbreak. “Like any family experiencing such a loss, we are heartbroken and have been managing as best we can,” Sinise wrote. He acknowledged the shared experience of loss that binds humanity together, expressing his deepest sympathies for anyone who has endured the death of a child or a loved one. The actor described the five-and-a-half-year fight as an “uphill battle,” yet he emphasized that Mac never wavered in his resolve to live a life of purpose.

Despite the physical toll of his illness, which included five major spinal surgeries and eventual paralysis from the waist down, Mac Sinise’s life remained anchored by his twin passions: service and music.⁴ He was a deeply integrated member of the Gary Sinise Foundation, serving as an assistant manager of education and outreach. His work there allowed him to channel his own struggles into empathy for others, particularly the wounded veterans and first responders the foundation serves.

However, it was through music that Mac truly found his voice during his final years. A graduate of the University of Southern California, where he studied songwriting and composition, Mac was a gifted percussionist and composer.⁵ Before his mobility was limited, he performed alongside his father as a drummer in the Lt. Dan Band, a group that travels globally to entertain and uplift service members. Even when the cancer robbed him of the ability to play the drums, Mac refused to let his creativity be silenced.⁶ He pivoted his focus to composition and arrangement, working tirelessly on a final musical project that would become his legacy.+1

In the months leading up to his death, Mac completed work on an album titled Resurrection & Revival.⁷ Gary Sinise shared that the family is now dedicated to ensuring this work reaches the world, with plans to release the album on vinyl as a permanent tribute to Mac’s artistry. The title of the album reflects the spiritual and creative awakening Mac experienced even as his physical body failed him. It serves as a testament to the idea that while the body may be finite, the art and the spirit one leaves behind can achieve a form of immortality.

The outpouring of support from the global community and the entertainment industry has been immense. Celebrities and fans alike have flooded the Sinise family’s pages with messages of love and solidarity. Angie Harmon expressed the collective sentiment, noting how deeply loved the Sinise family is, while Alyssa Milano offered prayers for strength during this unimaginable time. These messages underscore the impact Gary Sinise has had on others through his years of philanthropy, and the world is now returning that support in his moment of need.

Mac was laid to rest on January 5, following a private period of mourning for the family. In his final tribute, Gary Sinise spoke of the comfort found in knowing that Mac is no longer struggling. He described his son as a soldier in his own right—one who fought a war against a biological enemy with the same courage and dignity he admired in the veterans he spent his life serving. The story of Mac Sinise is ultimately not a story of cancer, but a story of a young man who chose to spend his limited time creating beauty and serving a cause greater than himself.

The Gary Sinise Foundation continues its mission, now fueled by the memory of Mac’s dedication. The release of Resurrection & Revival will likely serve as a focal point for the foundation’s upcoming outreach, reminding others that even in the face of an incurable diagnosis, there is a profound power in the act of creation. Mac’s life reminds us that the measure of a journey is not found in its length, but in the depth of the love shared and the art left behind. As the Sinise family navigates this period of grief, they do so with the knowledge that Mac’s “uphill battle” has ended in peace, and his music will continue to play for years to come.