following the death of his son, McCanna Anthony Sinise, who died from cancer at the age of 33.The actor made the news public on Tuesday with a post on his Gary Sinise Foundation website, noting that Mac passed away Jan. 5 and was laid to rest Jan. 23.“Like any family experiencing such a loss, we are heartbroken and have been managing as best we can,” the 68-year-old wrote under a photo of Mac, captioned: “In Honor & Memory McCanna Anthony ‘Mac’ Sinise, 1990-2024.”“As parents, it is so difficult losing a child.