Let Go made Lavigne the youngest female soloist to reach #1 in the UK, and the album was certified four-times platinum by the Recording Industry Association of America. As of 2009, over 16 million copies had been sold worldwide, more than 6 million of which were sold in the United States. Her breakthrough single, "Complicated", peaked at #1 in many countries around the world, as did the album Let Go. Her second album, Under My Skin, was released in 2004 and was her first album to peak at #1 on the U.S. Billboard 200 , eventually selling more than 10 million copies worldwide. The Best Damn Thing, Lavigne’s third album, was released in 2007. This album gave Lavigne her third #1 album in the UK Albums Chart and featured her first U.S. Billboard Hot 100 #1 single, "Girlfriend". Lavigne has scored a total of five #1 singles worldwide, including "Complicated", "Sk8er Boi", "I'm With You", "My Happy Ending" and "Girlfriend". With more than 30 million copies of her albums sold worldwide, Lavigne is currently one of the top-selling artists releasing albums in the U.S., with over 10.25 million copies certified by the RIAA. Her fourth studio album, Goodbye Lullaby, will be released in March 2011.
Lavigne branched out from recording music, pursuing careers in feature film acting and designing clothes and perfumes. She voiced a character in the animated film, Over the Hedge, in 2006. That same year, she made her on-screen feature film debut in Fast Food Nation. In 2008, Lavigne introduced her clothing line, Abbey Dawn, and in 2009, she released her first perfume, Black Star, which was followed by her second perfume, Forbidden Rose, in 2010. Her third fragrance is due out in August 2011. In July 2006, Lavigne married her boyfriend of two years, Deryck Whibley, lead singer and guitarist for Sum 41. The marriage lasted a little over three years, and in October 2009, Lavigne filed for divorce. Whibley and Lavigne have continued to work together after the divorce, with Whibley producing her upcoming fourth album, as well as Lavigne's single, "Alice", written for Tim Burton's film Alice in Wonderland.