Throughout the sonata that was Amy Tobin's life, her violin was always at the ready to express what she couldn't put into words.

The vibrant sound of her instrument resonated at concerts in Duluth and St. Paul Civic Symphony performances, where she served as concertmaster. But the notes also captured her love for her son and her drive to beat back cancer for him.

The North Oaks violinist who later became an Allina Health Systems medical technician died Jan. 14 at age 47. Her love for the violin reverberated through her life.

"It was probably an extension of her soul," said her sister Lisa Tobin, 56, of Minnetonka.

Tobin grew up in North Oaks and taught herself to read the newspaper at 3 years old, her family said. She kicked off her music career with piano. She picked up the violin at about 9 years old, said her mother, Marie Tobin.

Her sister said that Tobin fell in love with the instrument, performing in the Greater Twin Cities Youth Symphonies and attending camps like Interlochen Music Camp in Michigan. After graduating from St. Paul Academy in 1987, Tobin headed to Boston University and in 1991 earned a degree in violin performance with a minor in math.

After college, she immersed herself in the reggae genre, playing in Jamaica and Florida for a few years. She then moved back to Minnesota and worked as a shop manager at Fein Violins in St. Paul.

She gave birth to her son, Liam, in 2006. Tobin took over as acting concertmaster for the volunteer St. Paul Civic Symphony orchestra in the 2008-09 season and became official concertmaster the next season. Many people view the concertmaster as the most important position in the orchestra, said Jeffrey Stirling, director of the St. Paul Civic Symphony.

"Amy had a way of kind of getting across that message of high standards without making it seem unattainable or in any way demeaning," Stirling said.

Tobin took her violin skills around the state, playing in the professional Duluth Superior Symphony Orchestra and a tango group, and performing wedding gigs and Civic Symphony solos. She was diagnosed with breast cancer in 2008, but beat it into remission.

In 2011, Tobin's brother, James, died at 52 from a heart attack. It was a turning point for Tobin to return to school, realizing that she needed to support her son and wanted to pursue her passion for the sciences.

She graduated summa cum laude from Argosy University and took a job at Allina Health Systems as a medical technician. Just as she was beginning her job with Allina's Ramsey clinic, more bad news: The cancer had returned.

When she would wipe out cancerous spots in one part of her body, they would pop up elsewhere. Lisa said she and Tobin would call it "Whac-A-Mole."

Last Mother's Day, Tobin had terrible stomach pains but went onstage to perform with the Civic Symphony, even after her mother told her to skip it. She played beautifully anyway, her mother said.

"She is the bravest person I've ever known," she said.

Tobin died on her son's 11th birthday, and the two were "as close as mother and son could be," Lisa said. Liam plays French horn and cello, which his mother would insist wasn't a hand-me-down of her skills. Instead, she'd reply: " 'No, Liam has his own talents.' "

Tobin is survived by her son, sister, mother and father, John Tobin, of North Oaks. Services have been held.

Beena Raghavendran • 612-673-4569