Speaking to ET's Brooke Anderson at the Critics' Choice Movie Awards red carpet on Thursday, Hawke said of the nomination, "Everyone wants to turn these things into a race, but I try to look at it all like a big victory lap."
And it's not hard to see why the film means so much to Hawke. As the 44-year-old actor explained, "The first time I was ever nominated [in 2002 for Training Day] my son had just been born… and then today he was turning 13."
"Right after he was born was when Richard Linklater first approached me with the idea of Boyhood," Hawke added. "I've been working on it the whole of [my son's] life. Today was his 13th birthday and we got an Oscar nomination for Best Picture. It's so cool!"
Boyhood also got a lot of love Thursday night at the Critics' Choice Movie Awards, where it won Best Picture, Linklater took home the award for Best Director and Patricia Arquette won for Best Supporting Actress.