10/29/2007 at 01:00 AM EDT
I wasn't suicidal, but I never had much of a will to live [for] a long time," Colin Farrell
told Britain's Daily Mirror
newspaper last year. "Now I want to watch my son grow up.... He is the greatest priority in my life."
That devotion was evident in a revealing interview Farrell, 31, the nightlife legend and star of Alexander
and Miami Vice
, gave to Ireland's Sunday World
newspaper on Oct. 14. Disclosing for the first time that his son James has Angelman syndrome, a rare neurogenetic disorder that slows development and impairs speech and motor skills (see box), Farrell said he felt "incredibly blessed" by parenthood. "The only time I'm reminded that there is something different about him—that he has some deviation of what is perceived to be normal—is when I see him with other 4-year-olds," he said. "From day one I felt that he's the way he's meant to be."
Certainly there were plenty of skeptics who doubted whether Farrell was ready to be a father. (James's mother is model Kim Bordenave, whom the actor dated briefly in 2003.) After earning a doctorate in hard partying—for years, it seemed, he seldom met a woman he didn't want to nuzzle, and, on one particularly wild night, he broke his heel and wrist falling down a flight of stairs—Farrell entered rehab for a dependency on prescription medication in '05.
Since then, the actor—who has been dating Dublin student Muireann McDonnell, 21, for almost a year—has been more doting father than playboy. On his frequent trips with James to Miami, a city Farrell grew to love while filming Vice
in 2005, "Colin holds James on his belly and looks in his eyes—it's the sweetest thing you've ever seen," says a source. "It's like there's nothing in the world but father and son."
And like any proud father, Farrell couldn't help but share the recent moment when James took his first steps. "It was four years in the making," he told the Sunday World
. "It was incredibly emotional. There wasn't a dry eye in the house."