"I've been thinking about that recently, the last couple days," she told MTV News at a junket for the film. "I thought, 'What would her reaction to that be?'
"I feel proud of this movie, and I feel like I could stand behind it when she grows up and says, 'What were you doing for those two months in Pennsylvania?' I feel like I could say, 'This is what I made.' "
The film, which opens on New Year's Eve, may be too dark for a child to see, but much of Williams' post-"Dawson's Creek" work has been thought-provoking, something she said she'll be proud to share with her daughter someday.
"And I feel like that with most of my work now: I feel like I'm excited for the day when she's old enough to see it, because my aim is to make her proud that the time I spent away from her wasn't in vain," she explained.
While any mother/daughter viewings of "Blue Valentine" are yet to be determined, right now the pair is happy watching more family-friendly fare.
"She kind of lives in a Mary Poppins world," Williams said. " 'Singing in the Rain' is our current."
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