An US Weekly source described the nuptials as "very small and quiet."
Heigl tweeted Monday about a wedding in upstate New York, sharing a photo of herself with her husband, Josh Kelley, and former "Grey's" costar Kate Walsh.
US Weekly added that Knight didn't appear on stage for Friday and Saturday's showings of his off-broadway "Romeo & Juliet" production in New York City. His costars Elizabeth Olsen and William Hurt reportedly "wished they could go too, but they all congratulated him."
The news of Knight's wedding comes just as Ellen Pompeo opened up about some of the show's off-screen drama, which made headlines following Knight's departure and Heigl's supposed attitude problems.
“When Katie left, it was tough,” she told The New York Post. “You could understand why she wanted to go -- when you’re offered $12 million a movie and you’re only 26. But Katie’s problem is that she should not have renewed her contract. She re-upped, took a big raise and then tried to get off the show. And then her movie career did not take off.”
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