Colin Farrell’s Quest for a Cure

Omg Goddess

Celebs stopping by late-night talk shows to promote their upcoming films are nothing unusual, but Colin Farrell made his appearance on the "Late Show With David Letterman" personal on Thursday night.

In addition to giving Dave and his viewers the scoop on his latest movie, the horror flick "Fright Night," the 35-year-old actor also opened up about a cause that's close to his heart, Angelman Syndrome, a condition his 7-year-old son James was diagnosed with at age 2. The disease, which affects about one in 30,000 children, according to Colin, is marked by developmental delays, seizures, and speech impairment.

"My boy happens to be very highly functioning. He doesn't have any verbal speech but he walked just short of his 4th birthday and he's an incredibly happy child," he explained. Colin's son smiles so much, in fact, it was one of the reasons doctors suspected he had Angelman Syndrome,which is also characterized by constant laughing and smiling. Since the syndrome is often confused with Autism or Cerebral Palsy, the fact it's so much less prevalent hurts when it comes to raising money for a cure. "There's not that much funding because it doesn't benefit the pharmaceutical companies, of course," he said.

", if you want to go there and throw a few dollars down," Colin added, prompting applause from the audience.

We're guessing the site got plenty of new clicks last night .. and here's hoping for more.

Take a look at Colin's interview with Letterman ...

More Celebrity Features on Yahoo!:
Farrell's Son Diagnosed With Angelman Syndrome
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Celebs Do Late Night Right

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