Depression, like autism, is a brain disorder. They are believed to be biologically linked, said Lainhart, who works with the Utah Autism Research Program. She found in a new study that 25 percent of high-functioning autistic children have or are on the edge of clinical depression.

"When depression kicks in, even the person who has the best of situations on earth perceives that life situation as horrible, hopeless and all of that," she said.

J.J. loved sports. He ran on the high school cross country team. He played youth baseball and basketball. Due to his autism, he was always the smallest player on the team, but he had no fear. He gave his all.

"He played hard in basketball even though his size was against him," said George Serassio, a junior high school teacher.

J.J. spent hours in the driveway shooting hoops. He wouldn't go inside until he made 100 or 200 shots, whatever number his brain fixated on. Often he practiced without a shirt, which meant either sunburn or frostbite because he couldn't distinguish hot and cold.

"He could always school me in basketball," said friend Bryce Cutler, who stands a foot taller.

When J.J. was 14, his basketball coach kept him on the bench during a championship basketball game, saying he didn't want him to get hurt, though he played in two previous games against the same team. In high school, coaches told him he was too small for the squad.

"That's J.J.'s whole story," Darla Serassio said. "If you don't fit into a certain mold, you have no worth."

J.J.'s size bothered him. While his autism might have gone unnoticed, his slight build did not. Other children, even in high school, often referred to him as " 'ittle boy."

It embarrassed him as a teenager to shop in the boys' section. It disheartened him to be lumped with the 12-year-old deacons in his LDS ward rather than the 16-year-old priests. He took offense at a church leader who told him he was too short to see over the sacrament table. He never did get the chance to bless the sacrament.

The Sunday before he died, he told his parents he was finished going door to door to collect church fast offerings, which is primarily a deacon's job.

What he lacked in size, he made up in tenacity.

The final blow for J.J. Serassio started with a boxing match.

Last fall, he and friends turned to the sweet science, lacing up boxing gloves for some backyard sparring. He came home with a broken nose. The doctor scheduled surgery for the following week when the swelling went down. It would be on the eve of the chemistry final.

J.J. had trouble coming out of the anesthesia and didn't make it to school the next day. His mother's pleas to the teacher to allow him to make up the test fell on deaf ears.