Gary Sinise Has Remained 'So Strong' After Death of Son Mac, 33, from Cancer, Says Friend

Actress Kelly Carlson and more stars sent "love and strength" to the actor after news of his son's death

Hollywood is showing support for Gary Sinise after the actor shared that his son McCanna Anthony “Mac” Sinise died at age 33.

On Tuesday, Sinise said in a message on the Gary Sinise Foundation's website that Mac died from cancer on Jan. 5, and was laid to rest on Jan. 23.

"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," the Forrest Gump actor, 68, wrote. "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."

On Instagram, several stars reached out to send thoughts to Sinise and his family.

Angie Harmon wrote, "We are so sorry Gary. You & your family are deeply loved by so many. We are praying for all of you. Love you so very much." Alyssa Milano commented, "I’m so sorry, Gary. I’m praying for your family. And sending you love and strength."

Related: Gary Sinise's Son, McCanna Anthony 'Mac' Sinise, Dead at 33: 'Our Hearts Ache'

Robert Patrick wrote, "Gary all my deepest sympathy, sending love and prayers," while Katharine McPhee Foster said, "Oh Gary. I’m so sorry." Mary McCormick wrote, "I’m so sorry. Praying for your family."

Singer Alec Benjamin recalled knowing Mac in college, writing, "So sorry!!!! I went to [University of Southern California] with Mac. he was such a nice guy and so talented!"

Actress Kelly Carlson wrote on Instagram that Sinise "has been so strong through it and has managed to care for others as well."

She continued, "Dan and I send our deepest condolences and love. Gary you’re a remarkable man. For those that know him or even have just met him, know what I mean. One of a kind. Wishing Mac a beautiful journey and healing for his family. Just sending out some love from your friends back West. We miss you."

In his Tuesday message, Sinise, who is also dad to Sophie and Ella, said Mac's diagnosis of a "very rare cancer" known as Chordoma came in August 2018, just months after his wife Moira Harris received a stage 3 breast cancer diagnosis.

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories. 

While Moira went into remission and has remained cancer-free following treatment, Gary wrote that Mac's disease spread over time and "disabled him more and more as time went on."

"Our family's cancer fight lasted for 5½ 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 added. "He fought an uphill battle against a cancer that has no cure, but he never quit trying."

For more People news, make sure to sign up for our newsletter!

Read the original article on People.