Maguire, who has been trying for a year to get pregnant naturally with second husband Gareth Maguire, 28, admits her sister's ordeal concerns her. "I'm 33 and I realize fertility's not a given, it's a gift." Diagnosed last December with endometriosis, she underwent laparoscopic surgery to remove the growths and improve her chances of conceiving. So far she's not ready to take any more proactive steps, noting her older sister Julia, 35, an administrator at Stanford University Law School, easily conceived her two kids in her 30s. "There's no reason to get aggressive yet," she says.

For all three Chicks the embrace of music and family has always been tight. Martha and Emily Erwin, daughters of music-loving teachers Paul (country) and Barbara (classical), grew up in Dallas, where dad was headmaster of a private school. They studied violin at home and joined a kids band by the time they were teens.

In 1989 the sisters formed the Dixie Chicks with Robin Macy (guitar) and bassist-singer Laura Lynch. (The name comes from Little Feat's '70s hit "Dixie Chicken.") Even as Emily finished high school -- "She faxed her calculus homework in before gigs," says Martie -- they played street corners in spangled cowgirl garb, with Emily on banjo and Martie on fiddle. "In our first hour," says Emily, "we collected $375. So we thought we might want to do something with this."

Maines, meanwhile, grew up in Lubbock, Texas, one of two daughters of veteran sessions pedal steel player Lloyd Maines and his wife, Tina. Natalie was, says Lloyd, a born belter: "Even at 6 she could sing totally in tune and hear harmonies. She absorbed everything. She was fearless."

After graduating from high school in 1991 she briefly attended several colleges, including Boston's Berklee College of Music. "No one knew what country or bluegrass was, so I became the country flag-waver to be different."

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