There are some who will think "Silver Linings Playbook" is about ballroom dancing or the Philadelphia Eagles or a dysfunctional family. But underneath the surface quirkiness, it's actually a story about a family dealing with mental illness. And as director David O. Russell revealed, he knows that subject intimately.

Russell explained to TODAY's Jenna Bush Hager that his son Matthew (who has a small role in the film) has had to deal with mood disorders since he was very young. "Nothing comes easily to him, and that makes your heart bigger," he said. "It was a very healing thing to have written the movie ... I learned a great deal about resilience and about the relationship between the father and the son."

Oscar voters seem to feel it's triggered a chord; not only did Russell get a best director nomination, but it's the first movie in 31 years to be nominated in all four acting categories. And while that's gratifying, he says what's more important is that the film has brought him closer to his son. 

"It's a very healing thing that I think will be a touchstone for the rest of our lives," he said. "(This story) we know personally that is filled with hope and shines the light on it and says you don't need to be ashamed of this. You can own it, and you can heal it."

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