United Kingdom, May 14 -- Gary Sinise isn't sure if he'll return to acting after his son's death.

The 'Forest Gump' star - who hasn't appeared on screen since 2020 - decided to step away from Hollywood that year during his late son Mac Sinise's battle with cancer to focus on helping his boy.

He told PEOPLE magazine: "That's when I stopped acting. I started putting everything I had into trying to find a miracle for Mac."

Mac - who was diagnosed with a rare form of spinal cancer in 2018 - died aged 33 last year.

His father - whose most recent roles were in '13 Reasons Why', I still Believe' and 'Joe Bell' - is concentrating on his family rather than thinking about an acting comeback.

He said: "Something may come along and it'll be righ...