In her nine years of life, Krystie Anna Karl-Steiger never spoke a single word, but she expressed her love and emotions through her eyes and her smile. She was often most animated on Wednesday nights, when she sat among the choir during practice at Calvary Baptist Church in Roseville. Krystie was partial to male voices, the deep baritones, and to songs with rhythm.

So it was fitting that the choir gathered around her tiny casket topped with pink and white roses Thursday night, their voices soaring as they sang "He Never Failed Me Yet."

Krystie suffered and died from a rare disease, Tay-Sachs, but her life was by no means tragic. She traveled the country, from California beaches to the trading floor on Wall Street, with her two dads, Bruce Steiger and Rick Karl, and she lived longer than anyone else with the disease, nearly twice as long as expected.

On Friday, her dads and the nurse who cared for her for so long, Patty Beaudry, sat in a Minneapolis condo and talked about their remarkable story. The living room was crowded with toys and an empty crib still stood by the window. Beaudry held a stuffed pig and lamb, the same ones Krystie held in a photo taken the day before she died.

Steiger had always wanted kids, lots of them, and he told Karl that on one of their first dates. They tried and failed six times using a surrogate mom and eggs from a donor. The donor they selected seemed perfect: she was tall, blond and athletic, and seemingly very healthy. She had been valedictorian of her class.

What they didn't know is that she also carried a single enzyme that could cause Tay-Sachs. The donor didn't fit the profile of a Tay-Sachs carrier, so she was never tested. Besides, both parents need to carry the enzyme in order for their offspring to be born with the disease. Both fathers had donated their sperm, so the odds that two of the three had it were astronomical.

"Like hitting the Power Ball in reverse," said Karl.

When Krystie was born, her parents were ecstatic and filled with wonder. After a few months, Karl and Steiger began to notice she was not developing like other children. She couldn't sit up or crawl. Her parents began a battery of tests and an MRI found an abnormality. But it wasn't until an ophthalmologist saw the telltale cherry red dot in the back of Krystie's eye that they knew what was wrong.

"He closed the door and said, 'I'm so sorry,' " said Steiger.

Steiger went home and googled Tay-Sachs. "It was horrible."

The cherubic face and long eyelashes that make her look angelic were classic signs of the disease. Her chances of living past age 4 were not good. Karl and Steiger went to a convention on the disease and saw the condition of the Tay-Sachs kids just a year older than her and were scared at their already deteriorating condition.

The parents discovered an experimental cord blood transplant program at the University of Minnesota. Doctors were divided on whether they should put Krystie through the horrible process, which included chemotherapy and lots of steroids. Karl and Steiger decided there was little to lose and made a difficult decision.

So, the family came to Minnesota from their home in California and lived at the Ronald McDonald house for 18 months before buying a condo. "Nobody else knew how to deal with her," said Steiger.

Some Tay-Sachs kids rarely leave home after the first year, "but we were going to give her every life experience we could because we knew her life span was limited," said Steiger. "I don't know how much she absorbed of life. You could tell when she was content."

Beaudry, a nurse at the clinic, became closely attached to Krystie and the family and accompanied them on outings and trips and took care of her when they needed a break.

"She had a precious, perfect little face," said Beaudry, "and she was the best snuggler ever. If you held her in your arms, the rest of the world would just melt away."

"When it came to enzymes, Krystie was screwed," Beaudry said. "But she rocked it in the dad department. I have never met two more dedicated and caring parents. They were fierce advocates for her, and they never talked about her having a fatal illness. They just said they were going to treasure every moment they had with her."

Together, they went biking and rollerblading, with Krystie secured in homemade rigs. They participated in the St. Paul Classic bike tour three times. They traveled to 20 states together and swam in the Atlantic and Pacific oceans. They flew on planes, taking suitcases full of medicine and gear, so frequently the TSA agents knew them by name. At Tay-Sachs gatherings, "she was the diva," said Steiger. On Halloween, they would dress Krystie up in elaborate costumes such as Princess Leia for trick-or-treating.

Normal kid stuff.

Karl and Steiger have been active in Tay-Sachs education and fundraising and started a foundation that has raised $3.7 million for research (tinyurl.com/phvdaw). On Friday, both men talked about how good they had become at raising a special-needs child, and wondered if they might want to adopt a child that needs more attention.

"They had a daughter, and they were going to do everything you do as a family," said Beaudry.

"You play the cards you get dealt," said Karl. "Some people fold. We just kept dealing more cards. I wouldn't change it. She was perfect the way she was, except for one freaking enzyme."

"Krystie taught us to be more selfless," said Steiger. "She looked at you like you were the most important person in the world. Now that she's gone, we're going to be so lost."

"She took up an inordinately large part of the universe for such a little girl," said Karl.

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