Long before young girls were dressing in shawls and long dresses, imitating their hero Stevie Nicks, young Stephanie Nicks was dancing around her room in her Olympus Hills house, with a cape, imitating the nuns at the old St. Mary of the Wasatch Catholic High School.

Before Stevie Nicks was writing No. 1 songs and touring the world with Fleetwood Mac, Stephanie Nicks was strumming her guitar on her bed in Utah and writing poetry.

And before Stevie Nicks displayed her baton-twirling skills for the University of Southern California marching band — and for the world in the video for "Tusk" — Stephanie Nicks was teaching Karen Thornhill how to twirl a baton at Wasatch Junior High School.

To the general public, Stevie Nicks is rock royalty. But to Thornhill, Nicks is still the girl who moved to Utah from Texas in 1961. "She was a little shy at first, being the new kid in town and not knowing anyone," Thornhill said, describing Nicks as a "typical, normal, boy-crazy junior-high girl."

But even then, it was evident, "She was just born with this gift. Writing lyrics . . . poetry. I don't remember her ever without a pen in her hand."

Nicks only lived in Utah a little over two years. But during that short time, she and Thornhill formed the kind of lifelong bond between girls that can never be broken. It was a tough goodbye for the two girls when they found out Nicks was moving to Arcadia, Calif. "We sat on the curb and cried and vowed to stay close and together," Thornhill said.

True to their word, Thornhill went to stay with Stephanie in California the following summer and routinely visited in the years that followed.

It was also around that time that Nicks got involved with a band and returned to Salt Lake City to play at the old Terrace Ballroom on State. Nicks played with a Bay area rock band called Fritz from 1968 to 1972. One of her bandmates in that group was Lindsey Buckingham.

After Fritz ended, Nicks and Buckingham recorded their own album, simply titled "Buckingham-Nicks." In 1974, the "Buckingham-Nicks" album caught the ear of Mick Fleetwood, who was in the process of revamping the line-up for his band Fleetwood Mac. At the time it included himself and the duo of John and Christine McVie.

Fleetwood hired both Nicks and Buckingham, and the rest, as they say, is history.

Saturday, Fleetwood Mac returns to Salt Lake City for a concert in the Delta Center. The classic Mac lineup is now a quartet as Christine McVie decided to retire after the band's reunion tour in 1997. Following Saturday's show, Thornhill and her husband have been invited to hit the road with her childhood friend for a few shows. She says she has been fortunate to travel with Nicks and Fleetwood Mac on several tours, even taking her two young daughters with her.

Thornhill and Nicks still e-mail and keep in contact regularly. Although their career paths may have differed, they do not see one person's life as more important than the other's. In fact, Thornhill said the two "share a balance" and get the best of both worlds from each other.

When she goes on the road with Nicks, Thornhill gets to experience firsthand the life of a rock star. Thornhill, who has similar hair to Nicks and is about the same height, was once even asked by Nicks to don a pair of sunglasses and sign autographs in her place as she slipped out a back door.

But Thornhill and Nicks see each other as equals. They are still the same soul sisters they always have been for the past 30 years. "Stevie was my girlfriend first. She wasn't Stevie Nicks of Fleetwood Mac," said Thornhill, who cites "Landslide" as her favorite Mac tune. "We've shared our heartbreaks with each other. Mine were as important to her as hers to mine. My best friend is a rock icon, but she is still just Stevie. She is very sweet, very mellow. She is so genuine."

Nicks once told Thornhill, "Don't ever envy my life and not be appreciative of what you have."

For Nicks, her life is devoted to music and her career. Thornhill doesn't believe Nicks will ever marry because she doesn't want to give only a half-hearted effort. "She was born with a gift and she chose to follow that star. She gave her all to do this."

If you go . . .

What: Fleetwood Mac

Where: Delta Center

When: Saturday, 8 p.m.

How much: $29.50-$125

Phone: 325-7328

Web: www.ticketmaster.com

E-mail: preavy@desnews.com