Ryan Miller / Invision/AP 1 / 2
Ryan Miller / Invision/AP 1 / 2

TR Knight is a married man! The former "Grey's Anatomy" star has tied the knot with his longtime boyfriend Patrick, sources reveal to Us Weekly. The pair said "I do" on Oct. 4 in an intimate ceremony in front of family and friends.

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"It [was] very small and quiet," an insider reveals to Us. One of the more famous faces to attend? Knight's former ABC co-star and close friend Katherine Heigl flew in for the ceremony, the source says. No other details on the fete were immediately available.

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Knight, 40, is currently playing the role of Mercutio in the Classic Stage Company's off-Broadway production of William Shakespeare's "Romeo & Juliet" in New York. Knight's A-list co-stars in the include Elizabeth Olson and William Hurt. "[The] cast wishes they could go too, but they all congratulated him," the source adds. Knight was noticeably absent from the Friday and Saturday showings to celebrate the big occasion.

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Knight is best known for playing Dr. George O'Malley on Grey's from 2005 to 2009. He's also appeared on Law & Order: Special Victims Unit, The Good Wife and the film 42.

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