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The divorce petition was filed July 29 in the couple's hometown of San Mateo, California, Rolling Stone reports, and a hearing will be held Dec. 12.

Pegi became Neil's background singer in the early '90s after already inspiring some of his most popular songs, like "Such a Woman," "Once an Angel" and "Unknown Legend," which tells the story of when the two met. Pegi was a waitress at a diner near Neil's California ranch, where he would visit to see her.

"I used to order just to watch her float across the floor," he sang in the 1992 song. "She grew up in a small town/Never put her roots down."

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Pegi shared the stage with Neil at the 1994 Academy Awards and accompanied him on numerous tours over the past 20 years. They also co-founded the Bridge School in 1986, a school for children with severe physical limitations. The organization was inspired by a lack of educational opportunities for their son, Ben, who suffers from cerebral palsy. Neil and Pegi hold a benefit concert for the Bridge School every year, hosting a lineup of all-star musicians, like Guns N' Roses, Sarah McLachlan, the Flaming Lips and Foster the People, in Mountain View, California.

Pegi has released three solo albums since 2007 and has toured mostly on her own, though occasionally with Neil on guitar. Their last performance together was in October 2013 at a benefit concert for the Bridge School. This year's benefit is still scheduled for Oct. 25 and 26, according to the school's website.

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Neil recently finished a European tour and both he and Pegi were slated to play in Raleigh, North Carolina, on Sept. 13, though Pegi's name has been removed from the lineup.