Mary Anna Culligan, a costume designer who had worked at Children's Theatre Company in Minneapolis since 1985, died unexpectedly May 23 at her home.

She recently had been diagnosed with hypertrophic cardiomyopathy, a condition that involves thickening of the heart muscles.

"We believe that cardiac arrest was the cause of death," said Judy Culligan, her sister.

Culligan, 52, was known as a quiet person who was loudly expressive in her costume designs.

"She was forever working her magic," said Cathie Drake, who worked in the company's costume shop with Culligan for many years. "Some people like to make costumes as cheaply as possible because they have no money. But Mary relished taking something from a thrift shop or off a secondhand shelf and transforming it into this fabulous Scandinavian period piece for 'Pippi Longstocking.' "

Culligan was born in 1961 in San Bernardino, Calif., to a businessman father and schoolteacher mother. She moved with her family in 1966 to Sheldon, Iowa, just outside Sioux City. There, her father, a son of one of the founders of Culligan Soft Water, was set up with a Culligan dealership.

Culligan's interest in theater was clear early on.

"Since she was the oldest of the three of us, she'd always make up games for us to play, and draw pictures," Judy Culligan said. "She would be the director, telling us what to play."

She also had an interest in painting. Culligan decided to combine her love of theater, which she studied at the College of St. Benedict, with her art.

"Her gift was her ability to transform found objects and create things from nothing," said Deb Shippee, costume director at the company. "She had this amazing ability to see extraordinary things in ordinary things that other people overlooked."

Culligan also worked at such small Twin Cities theaters as Mary Worth and 15 Head Theatre Lab, which she co-founded. She also collaborated with a number of national figures, including author and illustrator Tomie dePaola, whose "Strega Nona" children's books were staged at Children's Theatre.

"I am devastated by the news," dePaola said. "She was my right-hand person. When I met her, she was just 23, but she had this talent, this eye that made picture books came vibrantly alive onstage."

"Mary was an extraordinary talent and wholly original artist in addition to being a kind and wonderful person," said Children's Theatre Company artistic director Peter Brosius. "Her technical prowess, treasured by costume designers from around the country, ensured gorgeous costumes defined by visual richness and depth."

In addition to Judy Culligan, of Sheldon, Iowa, survivors include parents Marjorie and Jude Culligan, also of Sheldon; brother Chris Culligan of La Farge, Wis.; sister Ginger Culligan of Ashby, Mass., and several nieces and nephews.

The funeral will be private. A public celebration of her life will be held at the Children's Theatre at a later date.