Compared with the skin-bearing antics of other teen idols -- Britney Spears chief among them -- Avril Lavigne was a new kind of superstar, one whose appeal didn't rely on sexy videos or suggestive music. She further distinguished herself by bypassing the assistance of professional writing teams during the creation of her second album, choosing instead to collaborate with singer/songwriter Chantal Kreviazuk, Evanescence's Ben Moody, and Evan Taubenfeld (who had previously worked with Lavigne as her touring guitarist). Released in May 2004, Under My Skin was more serious than its predecessor, dealing with such issues as premarital sex ("Don't Tell Me"), depression ("Nobody's Home"), and the death of Lavigne's grandfather ("Slipped Away"). The album debuted at number one in more than ten countries, went platinum within one month, and further established Lavigne as a pop icon. Incidentally, a song that was co-written by Lavigne and ultimately cut from the final track list -- "Breakaway" -- was later given to Kelly Clarkson, who used it as the title track and leadoff single for her Grammy-winning sophomore album.

Lavigne married her boyfriend of two years, Sum 41's Deryck Whibley, in July 2006, just one month after the animated film Over the Hedge announced her cinematic debut (Lavigne voiced the part of Heather, a hungry opossum). She also appeared in Richard Linklater's fictional adaptation of Fast Food Nation, which was released that November. Nevertheless, she spent most of the year working on her third album, enlisting former blink-182 drummer Travis Barker to play drums and cherry-picking a variety of producers (including her husband) to helm the recording sessions. The Best Damn Thing appeared in April 2007, and its leadoff single, "Girlfriend," marked a return to the bratty, spunky punk-pop of her first album. "Girlfriend" soon became the subject of controversy as the '70s power pop band the Rubinoos sued Lavigne, claiming that her tune reworked their 1979 song "I Wanna Be Your Boyfriend." No amount of bad publicity could hurt the singer, however, as "Girlfriend" became her biggest U.S. single ever and The Best Damn Thing topped album charts worldwide. ~ Andrew Leahey, All Music Guide