Who is Mac Sinise? 5 Things About Gary Sinise’s Late Son – Hollywood Life

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Gary Sinise and his wife, Moira Harris, tragically lost their son, McCanna “Mac” Anthony Sinise, to cancer in January 2024. Mac was just 33. The CSI: NY alum is opening up about his late son’s death in his 2026 book, Graceful Warrior: The True Story of a Son, a Father, and a Family Who Carried Each Other Through, recalling that Mac lose his ability to breathe on his own during his final hours.

“The machine was breathing for him now,” Gary wrote. “I was so proud of Mac. I loved him so much. He had fought so hard, and I had fought with him, never letting thoughts of defeat creep in. Yet I could see that, despite all our efforts over the past few days, he would not return to the place where he could simply use a cannula to breathe.”

The Forrest Gump actor remembered his family’s emotional moment surrounding Mac before he died.

“Already I felt completely worn out, but I knew I needed to walk my family through this difficult and sacred day,” he explained in the book. “After everyone arrived, I took them into the private room and tried to tell them as best I could what the night and early morning had been like. It was tough for me, seeing all their faces.”

Learn about Mac’s life and tragic death here.

Mac Sinise’s Battle With Chordoma

In a statement shared via Gary’s foundation website, the father of three revealed that his son had been battling a rare form of cancer since 2018. “Then, on August 8th, we found out that Mac was diagnosed with a very rare cancer called Chordoma,” Gary penned. “What was happening? What is Chordoma? I had never heard of this.” This type of bone cancer is considered to be extremely rare and can affect both the spine and the skull, per the Mayo Clinic.

Mac underwent multiple surgeries to fight his cancer in the years leading up to his death. “With Mac, after surgery to remove the initial tumor in September of 2018, and another spine procedure in February 2019 to clear what looked like an infection, unfortunately a follow up scan in May of 2019 would show that his Chordoma had come back and was spreading,” Gary explained in the statement. Mac had a few more surgeries after that, along with radiation and chemotherapy.

Mac Attended the USC Thornton School of Music

As Gary once revealed, his son had an intense passion for music. Despite Mac’s battle with cancer, he continued to play instruments and work on his album in the months before he died. Although he was paralyzed from the chest down, Gary explained that his son had some mobility in his right arm and left hand. It was Mac’s mother Moira who suggested that he learn to play the harmonica since he could no longer play the drums. “He did, and it was beautiful,” the proud dad gushed on his foundation’s website.

Mac Is Survived by Two Siblings

Aside from their late son, Gary and Moira are proud parents to two other adult children. Their daughter Sophie Sinise was born in 1988, about four years ahead of her sister, Ella Sinise. Sophie followed in her father’s footsteps by becoming an actress and has a few movies listed on her IMDb page. In 2011 she appeared in Swamp Shark, and later appeared in The Heart of Christmas that same year.

Mac’s Mother, Moira Harris, Also Battled Cancer

Not only was Mac diagnosed with cancer in 2018, but his mother Moira was too. “The summer of 2018 was a particularly challenging time for our family,” Gary wrote on the foundation’s website. “In June of that year, my wife Moira was diagnosed with stage 3 breast cancer, and after surgery to remove lymph nodes, she began chemotherapy and radiation.” She went into remission after months of treatment and has been cancer-free since.

Gary Sinise Carried His Son With Him After Mac Died

“I could hear his voice, as if he were still talking to me,” Gary wrote in his 2026 book. “Mac and I stayed like that for a time, me just staring at him, studying him, remembering him.”

Gary added that he could “still feel” Mac’s personality.