Colin Farrell Opens Up About His Son's Angelman Syndrome on 'Letterman'

Colin Farrell appeared on Late Show With David Letterman last night to promote his upcoming movie, Fright Night, but also took a little time to give a shout out to CureAngelman.org and revealed that one of his sons has been diagnosed with Angelman Syndrome.

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Colin has two sons James, 7, and Henry, almost 2, and briefly discussed his family with David Letterman.

"James, just a quick shout out if I can, James has a condition called Angelman Syndrome and it only affects one in 30,000 children, they say," Colin said on Late Show. "So there's not that much funding because it doesn't benefit pharmaceutical companies, of course."

The actor asked for anyone to help by visiting CureAngelman.org to help donate and then discussed a bit more about his son and how he was diagnosed.

"It was actually when a doctor saw how happy he was," Colin explained. "He was like, 'Does he always smile this much?'"

James started walking just short of his 4th birthday and doesn't have any verbal speech, but Colin made sure to say that his boy is a "a really happy boy."

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Watch a clip of Colin's interview (via AOL TV), below!