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Though he's weathered his share of ups and downs in Hollywood and in life, nothing prepared Colin Farrell for bringing up his eldest son, James, who suffers from Angelman Syndrome, a genetic disorder. In an interview for the December issue of InStyle, Farrell said he "nearly broke in half" when James, now 9, took his first steps.

"We share in the smallest victories; the first words at age six or seven, being able to feed oneself at 19, and getting the seizures under control," he said. "When James took his first steps at age four, I nearly broke in half!"

Angelman Syndrome is characterized by seizures, jerky movements, sleeping problems, and developmental disability. The seizures can be treated, but there's no cure for the disease. For the first years of James' life, Farrell and Kim Bordenave, James' mother, coped in private.

"It was at the Special Olympics in Shanghai in 2007 that I decided, after consulting with James' mother, that I wanted to talk publicly about the pride and joy I had in our son," he said.

He has enriched my life, but I don't want to minimize the trials that so many families go through; the fear, consternation, frustration, and pain."

Farrell now works with the Foundation for Angelman Syndrome (FAST) to raise awareness and empower other families affected by the disorder.

"When you're the parent of a child with special needs, it's important to feel that you're not alone," he said.

InStyle's December issue also features Emma Stone, Ben Affleck, Josh Brolin, and Leighton Meester talking about causes that are close to their hearts.

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