The black-and-white music video showcases Portman's bump in a series of close-up shots, along with scenes of her swimming in a bikini. She's also seen sitting on a bed in lingerie, with one hand on her stomach.
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The lyrics seem to match the visuals of a woman preparing to give birth. "When I see my willing heart, how will I know?" Blake croons in the chorus. "How will I walk slow? How will I know?"
Portman shot the music video just days before she gave birth, according to a press release obtained by Pitchfork Media, but still had to back out of attending the Independent Spirit Awards and Oscars ceremonies, which took place around the time of her due date.
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When ET caught up with the Jackie star last month at the Screen Actors Guild Awards, she admitted to not having picked out a name for her baby yet.Read more at Entertainment Tonight