Gone Girl's Rosamund Pike is pregnant, and expecting her second child with boyfriend Robie Uniacke, her rep confirms to Us Weekly Credit: Karwai Tang/FilmMagic

Pike's precious cargo! Gone Girl's Rosamund Pike is pregnant, and expecting her second child with boyfriend Robie Uniacke, her rep confirms to Us Weekly.

The British actress, 35, and researcher Uniacke, 54, first met in 2009 and are already parents to son Solo, 2. Back in December 2012, she explained to Vogue why she and Uniacke never wed.

"You try to do the right thing and the conventional thing, and it doesn't work, and then you're free again," she said. (Pike was previously engaged to director Joe Wright, whom she met on set of Pride & Prejudice in 2005.)

"It is interesting to break all the rules," she continued to Vogue. "I'm not married, I have a baby, and it feels infinitely more right."

Pike (and her growing baby bump!) will soon be hitting the red carpet to promote David Fincher's Gone Girl with costar Ben Affleck, 41. The actors play spouses Nick and Amy Dunne in the film adaptation of Gillian Flynn's 2012 bestselling thriller.

Gone Girl hits theaters Oct. 3, 2014.