3. Writer/director David O. Russell and actor Robert De Niro, who plays Cooper's father in SLP, also related to the story on a very personal level. "If not for my son having issues of bipolarity, the book would not have grabbed me the way it did," Russell told the New York Daily News in regards to Matthew Quick's source novel. De Niro also has a child with special needs, and was similarly drawn to the story because of that. "If you're a father, you certainly understand what it's like to go through the worry about your kids, especially if they've got issues like Bradley's character has. Sometimes it can be overwhelming. It can be nightmarish and upsetting. There's nothing much you can do but deal with it." You can get a sense of how difficult such relationships can be in the trailer above.