Amy Winehouse is suing her former mother-in-law for copyright infringement, the Sun reports. Nope, Blake Fielder-Civil’s mum didn’t steal one of Winehouse’s songs—she sold a love letter from Amy to Blake, and the singer is “furious the private letter was used to make money,” a pal says. Winehouse is suing for nearly $82,000. (More Amy Winehouse stories.)