As his wife Mara slumped into a chair, Mark still remembers the time on the wall clock, 3:31 p.m., and the doctor''s next words: "He said what has to be the worst words you''ll ever hear in your life -- ''We won''t know for sure for 24 hours.'' "

The next day, the Horstman''s got the news: Kate had rhabdomyosarcoma, a rare, muscle cell soft tissue sarcoma. And then, a second punch: she needed treatment immediately. Had the family waited another three weeks to have the mysterious cyst treated, doctors said they would have lost their beloved daughter.

Thus began the family''s journey into cancer treatment, with two parents facing their worst nightmare and a kindergartner entering the scary and uncertain world of therapy, hospitals, megadoses of drugs and doctors. "I made two calls," Mark says, "one to my parents and another to a close friend, who was director of the University of Texas M.D. Anderson Cancer Center in Houston. My cell phone rang in one hour and it was set. On Monday, we were being treated.

Kate's treatment was part of an experimental study that involved drinking a cocktail of cancer-fighting drugs as part of a clinical trial. "We went to 11 funerals the first year she was treated in the study group," he sadly recalls. "She was in the half of the group that lived." One physician who helped treat Kate had also lost a daughter to the same cancer. "We now see him and weep," Mark says of the sad irony.

Kate says she remembers a lot about the experience, despite her young age. She''s 16 now, a cheerleader and a member of the high school varsity soccer team whose dream is to one day work for NASA. "I have no physical problems, I''m really lucky with that," she says. "Most of it is mental. I have a much deeper respect for illnesses and for people with pain and families with pain -- and a lot more awareness of cancer. I learned that you don''t get to throw anything away. You don''t wait for tomorrow."

Looking back, Mark says the life-altering experience forced him to dig deep and draw upon his spiritual roots. Living in the small town of Fredericksburg, Texas, the family was constantly amazed by the kindness of their community: casseroles left on the doorstep, their lawn perpetually mowed, their mail always picked up and free house calls by local doctors. And he found a new ally in the ACS.

When asked to chair the local Relay for Life, Mark immediately said yes. "Relay became a way to give back. I thought, 'Here's my opportunity.'"

Not only did Mark, Kate, Mara and two sons, Travis and Drake, give back, they excelled. Under Mark''s direction, the Fredericksburg Relay for Life has been the top fund-raiser in Texas for four years running. The first year, Mark''s goal was to raise $25,000 -- and he netted $45,000. And the figures kept increasing: $55,000 in 1998, $60,000 in 1999 and $70,000 last year. "I wish I had a dime for everybody who told me it could not be done," he says.

Today, Mark serves as a motivational speaker for the ACS, and travels the U.S. lecturing to local chapters about how to organize successful relays. He''s also started an email list for 650 relay participants across the US that helps promote the event with inspirational survivor stories and other fund-raising tips. "I can never repay the ACS, but I''m still trying," he says. "Five years ago, I didn''t even know relay existed. Now I''m training thousands of people. Relay has reconnected me with the spirit and heart and the real soul of people. It''s not about the money. It''s about what the money can do."