Exclusive: Stanley Tucci Is Engaged to Emily Blunt's Sister Felicity!

Stanley Tucci found love again!

The Devil Wears Prada actor, 50, is engaged to Felicity Blunt -- sister to actress Emily Blunt -- a source confirms to Us Weekly.

"Stanley is very happy with her," the source says of British Blunt, who works at a London literary agency.

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Tucci and bride-to-be Felicity were recently set up by her famous actress sister Emily, with whom he worked in The Devil Wears Prada.

"Emily loved Stanley on the set of Devil, and just thought they would hit it off, so she set them up," the source explains, adding that Tucci has been making frequent visits to London to be with her.

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It will be the second marriage for Tucci, whose first wife, Kate, lost her battle with cancer in April 2009. The spouses share three children together. "My wife was an extraordinary person who showed us all what great strength is," Tucci told the New York Post after her passing.

Explains the source of Tucci's bride-to-be: "It hasn't been easy for him getting into a new relationship, but Felicity is a lovely person and very warm and comforting." (Tucci, who does voice work for books on tape, shares a passion for literature with his new love.)

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The pair stepped out together Tuesday night at the afterparty for the fim Rampart held at Mondrian Soho in downtown NYC, where Blunt showed off a dazzling engagement ring.

With stars like Ben Stiller and wife Christine Taylor, Grace Gummer, Billy Crudup and director Abel Ferrara standing by, Tucci happily introduced Blunt as his fiancee and accepted plenty of congrats. "They looked completely content together," adds an observer.