Sienna Miller's Baby Bump Revealed on Red Carpet in NYC

Sienna Miller has kept a rather low profile after confirming in January that she is expecting her first child with boyfriend Tom Sturridge. But the mom-to-be picked Valentine's Day as the perfect day to debut her baby bump to the world.

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Sienna attended the video installation for The Ever Changing Face of Beauty by Solve Sundsbo in NYC last night at the Park Avenue Armory. The 30-year-old model/actress hit the red carpet in a black gown that flaunted her growing bump.

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Even though it was Valentine's Day, Sienna's boyfriend and father of her child, Tom, was not in attendance.

Rumors were circulating that Sienna and Tom are actually engaged, but Sienna was not wearing a ring last night.

Tom, who is best friends with Twilight star Robert Pattinson, began dating Sienna last year.