Forrest Gump star Gary Sinise shared the heartbreaking news of his son’s passing on the Gary Sinise Foundation‘s website and his Instagram page, revealing that the 33-year-old McCanna Anthony “Mac” Sinise lost his battle to cancer.

Mac was diagnosed with a rare form of cancer known as Chordoma on August 8, 2018, just three months after his mother was diagnosed with stage three breast cancer.

However, as his mother Moira’s treatment was successful, Mac’s condition only worsened over time, gradually robbing him of his mobility.

Gary expressed his immense grief for the loss of his loving son.

“Like any family experiencing such a loss, we are heartbroken and have been managing as best we can. 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. Over the years I have met so many families of our fallen heroes. It’s heartbreaking, and it’s just damn hard,” the heartbroken actor wrote.

“Our family’s cancer fight lasted for 5 ½ years, and it became more and more challenging as time went on. 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.”

A number of celebrities posted messages of support for Gary and his family on Instagram.

“We are so sorry Gary. You & your family are deeply loved by so many,” wrote Angie Harmon. “We are all praying for you. Love you so very much.”

Alyssa Milano, meanwhile, posted: “I’m so sorry, Gary. I’m praying for your family. And sending you love and strength.”

Mac’s life was a fulfilling one. He joined the Gary Sinise Foundation as an assistant manager of education and outreach and pursued his passion for music until the very end. He performed alongside his father in the Lt. Dan Band as a drummer.

Since his diagnosis, Mac had undergone five spine surgeries and was left paralyzed from his waist down, but he never stopped doing what he loved; making music. Just before his passing, he had completed work on an album Resurrection & Revival.

Mac studied songwriting and composition at the University of Southern California from where he graduated.

Gary said that the family is ensuring Mac’s album, Mac Sinise: Resurrection and Revival, is released and pressed on vinyl.

Mac was laid to rest on January 5.

We are so sorry for Gary Sinise loss. Our thoughts and prayers go to him and his family during this time of grief.