In November 2005, Bruce McClintock put on a red plastic bracelet emblazoned with the word "relentless." He donned the bracelet after his son, Todd, then 25, was diagnosed with acute lymphoblastic leukemia, an aggressive malignancy of the white blood cells.

Although his son survived only 17 months after that diagnosis, Mr. McClintock and his wife, Sue, of Upper St Clair, said they "remain relentless'' in their support for research to find a cure for the disease that took their son.

This month, the couple and their seven surviving children are hosting the first fundraiser in Todd McClintock's memory.

The family will host a Halloween-themed walk Oct. 18 at Gilfillan Park, next to Westminster Presbyterian Church on Washington Road in Upper St. Clair. The township park is a 60-acre farm and woodlands with a mulch trail.

The walk will be about 2.181 miles long, in honor of Todd's birthday: 2/1/81.

Activities for children, such as a soccer kick, will be set up along the trail.

Door prizes and a prize for the best costume -- costumes are optional -- will be given out. The family will donate all prizes and refreshments, but they also hope to secure corporate donations for the event.

Registration begins at 10 a.m. and the walk, which will not be competitive, begins at 10:30 a.m. Participants should register in advance at www.teamtodd.org.

There is no entry fee, but donations will go to the Leukemia and Lymphoma Society through the Todd Reed McClintock Memorial Fund. Donations can be made on the Web site or mailed to 1500 Valley Court, Upper St. Clair 15241. Checks should be made payable to the Leukemia and Lymphoma Society.

The couple plans to make the walk an annual event.

Halloween was one of their son's favorite holidays, his parents said.

"He loved a good costume, so we are honoring his memory by continuing that tradition," Mrs. McClintock said.

From the time of the diagnosis through months of aggressive medical treatment, family and friends remained dedicated to raising money to find a cure, she said.

Todd McClintock was diagnosed in late 2005, while living and working in Philadelphia.

Shocked by the diagnosis but hopeful for a cure, his parents rented an apartment in Philadelphia to be close to their son during his treatment. Mrs. McClintock spent a majority of the next 10 months there, while her husband visited and maintained his job at home. He is a certified public accountant at McClintock & Associates, a family business.

During those months, Todd McClintock would endure chemotherapy; a bone marrow transplant (his brother Dave and sister Kristin were donors); and brain and lung surgery.

Despite promising improvement, when Todd McClintock relapsed in August 2006, the family brought him home to Upper St. Clair. Here, he received more chemotherapy and a second "mini" bone marrow transplant. But by January, the leukemia cells had returned.

Todd McClintock received more treatment and in March 2007, he was healthy enough to attend a walk/run fundraiser for the Leukemia and Lymphoma Society in North Park. More than 150 friends and family formed "Team Todd," and donations in his honor totaled about $125,000.

Todd McClintock traveled the course in a wheelchair, pushed by his siblings and friends.

His parents describe the evening after the race as one of the best times of their son's life during that difficult period.

"It was so good to see him standing amidst a group of friends, laughing and talking," Mrs. McClintock said.

That night Todd stayed up late with his family, playing a board game.

"In retrospect, I wonder if he sensed that this event was the last -- that these hours of feeling quite well and hanging out with family and friends was, in a way, a goodbye," Mrs. McClintock said.

Her son died at home the following month.

Mrs. McClintock describes Todd as someone who quietly helped others and who was kind to friends and family. He enjoyed competing with his siblings in sports and engaging in adventures such as skydiving. He also was appreciative, she said, always thanking those who offered to help him.

The McClintocks said that support from the community has been invaluable to the family both during their son's illness and as the family continues to grieve.

Although his red bracelet has faded to a shade of pink, Mr. McClintock said he has no plans to take it off.

"When it falls off, I will replace it with a new one," he said. "That is what finding a cure for leukemia is all about ---- being relentless."