Outwardly Healthy Family Searches for Answers to Mysterious Deaths : Tragedy: Doctors have no explanation for the string of sudden fatalities. Survivors try to cope with the uncertainties.

A chill winter wind picked up loose dirt from the fresh grave of 15-year-old Franklin (Sonny) Santos. The soil swirled, then scattered on the nearby plots of his father, two uncles and an aunt.

Each of their hearts had stopped, leaving broken ones behind--and leaving a medical mystery as well.

Like the family patriarch, buried in his Guam homeland, all died young and suddenly--without warning, without reason and without last goodbys.

Surviving family members fear that they, too, could soon lie here. They have mourned at Cedar Lawn Memorial Park too many times.

“I know the grieving process well,” said Annette Soares, who lost her son in November and her first husband, Franklin Santos Sr., in 1985. “I try not to be afraid. But the whole family is thinking, ‘Who’s next?’ ”

Dr. L. Bing Liem, associate director of the cardiac arrhythmia unit at Stanford University Medical Center, tested one family member in 1985 and researched records of the dead relatives. But he has no clue to what is steadily killing the outwardly healthy Santos family.

“We found some enlarged cells and scarring around the heart in some of the autopsies, but nothing really conclusive,” Liem said. “And we can’t find anything before they die. I’ve never seen anything like it. It is a real mystery. But I think we have to keep looking for an answer.”

For now, family matriarch Donatila Santos Leonardo, who has lost a husband, four of seven children and one grandson to sudden death, looks toward God for hope and medical science for a miracle.

“My daughter Nina says nobody can help us now,” Mrs. Leonardo said. “I say we have to have faith in God. Who am I to go against God’s will? Maybe, one day, the doctors can help us.

“But there are nights I can’t sleep thinking about what causes this in people that are so full of life. You question yourself. Sometimes, when the phone rings, I just jump. Because I don’t know what to expect.”

The last time the telephone rang with bad news was Nov. 15, when Mrs. Leonardo learned that her 15-year-old grandson had died at his homecoming dance at Wilcox High School in Santa Clara. He collapsed while dancing.

His grandfather, 34-year-old Francisco Martinez Santos, died in 1960, four days after a physical examination showed him to be in good health. Mrs. Leonardo, who moved to the United States with her family more than two decades ago, said four of her first husband’s brothers also died of heart failure, two while in their 30s.

Sonny’s funeral was the family’s fifth in 10 years:

* 27-year-old Doris Santos died while taking a nap in 1981.

* 24-year-old Ronald Santos collapsed and died while playing softball in Sunnyvale in 1984.

33-year-old Franklin Santos died while watching television in his Sunnyvale home in 1985.

* 30-year-old Ralph Santos died in San Jose while on his sofa in 1987.

The graves of Ralph and Franklin and Sonny Santos remain unmarked. Sonny’s is also new. His father is still waiting for the military to pay. And the family apparently didn’t have the money or will to mark Ralph’s grave.

“With all the deaths, we have been really drained financially and emotionally,” said Nina Garrido, one of three surviving siblings. “At this point, we expect death, but it’s still hard.

“After my brother Frank died, I went in for tests. The doctor says I’m fine now, but he can’t guarantee what’s going to happen five minutes from now. It makes you live your life different. I appreciate every day I’m here.”

During two days of extensive testing at Stanford University, doctors twice stopped Mrs. Garrido’s heart to determine what might cause it to fail suddenly.

“I was dead for 14 seconds, but they brought me back,” said Mrs. Garrido of Manteca, shuddering at the memory. “After they didn’t find anything, everyone in my family figured there was nothing we could do. But with Sonny gone, we’re looking for answers again. We can’t lose our children too.”

Mrs. Garrido’s two children, Ann Marie and Brandon, don’t plan to undergo similar extensive tests unless doctors find some leads, however. Mrs. Soares’ surviving son, 11-year-old Roque, has agreed to the tests.

Doctors are hoping that new medical tests on Roque and on the late Doris Santos’ daughter, 14-year-old Shawnte, will provide some clues. Shawnte already has undergone some tests after fainting last year at church.

Dr. George Van Hare, her doctor at UC San Francisco, put her on medication after she fainted during a tilt test. He found a higher than normal level of glycogen, or sugar, in her heart muscles--which shouldn’t cause heart failure and could be a false clue, he said.

An abnormality in heart rhythms or the muscle often provide clues, Van Hare said. Doctors suspect that something must be wrong with the family’s genetic code, but tests aren’t sophisticated enough to discover it.

“We think it’s a dominant trait in the family. It doesn’t seem to skip generations,” Van Hare said, explaining that family members probably have a 50-50 chance of suffering from the hidden malady.

Mrs. Soares and her sons began talking with mental health counselors after her first husband died, although the rest of the extended Santos family hasn’t dealt with their emotions in the same way.

“I decided we had to go to counseling after Roque had such problems after his father died,” Mrs. Soares said. “The rest of the family are old-fashioned. “They think it’s taboo to go to therapy. I’ve accepted that Sonny is with God and is in good hands. But I’m not ready to lose my other son. And I’m tired of living with death.”