Then last month, Tracy police arrested long-time substitute teacher Jesse Llorente III and charged him with child pornography, and several counts of felonious lewd acts with a child.
The arrest came after fifth- and sixth-grade students in Tracy's George Kelly Elementary School reported he made them feel uncomfortable when he stroked their hair and shoulders.
Llorente, whose case is being played out in San Joaquin Superior Court alongside Huckaby's, pleaded not guilty Tuesday.
Just days after Llorente's arrest, Sandra disappeared. Her body was found 10 days later stuffed into a suitcase that had been thrown into an irrigation pond a few miles from her house.
So far, no motives have been offered in Sandra's death. The charges of special circumstances of rape, kidnapping and lewd acts with a child when accompanying a murder charge mean Huckaby could be sentenced to death if convicted.
Huckaby's 5-year-old daughter Madison was once Sandra's playmate. Police have told ABCNews.com they believe Sandra was killed shortly after being seen skipping across the street in her neighborhood, an image that has been ingrained in the minds of Tracy residents.
The San Joaquin District Attorney's office is prosecuting four cases from Tracy right now, according to Deputy District Attorney Robert Himelblau, the fourth being rape charges against plastic surgeon Peter Chi. Chi, 46, has not entered a plea but is accused of raping eight female patients and commissioning a lewd act with a 16-year-old, according to ABC affiliate KXTV.
But Himelblau told ABCNews.com in an e-mail that Tracy doesn't present his office with more crime than any other town in his district.
"I believe that Tracy has just hit a bad run of high-profile cases," he said.
The more violent circumstances of the cases -- from the shackled teen's apparent ongoing abuse to Sandra's alleged rape and murder -- are almost too much for some people to bear.
Stagmeier said extremely disturbed hearing the charge against Huckaby that Sandra was raped with a foreign object.
"I could have gone the rest of my life without the gory details," she said.
But now school officials have asked parents whose children may have spent time with Huckaby to question their children to determine whether others may have been assaulted. And things like that make residents worry what else could happen in Tracy.
"I kind of do wait for the next shoe to fall, unfortunately," Stagmeier said. "I wish it wasn't that way unfortunately."
And it makes her sad, because she said Tracy is the type of small town people hope to live in: Her family moved there about three years ago for a quieter life.
"I just hope that our town gets over this," she said. "I really think that it's just a bad stroke of luck."
Cardoza said the outpouring of support in the wake of Sandra's death has been stunning. The school district has received offers from around the country of psychologists for students and teachers and for benches, trees, gardens and murals in Sandra's name.
Long's Drugs, an area pharmacy chain, even sent over Easter baskets for Sandra's entire second-grade class at Jacobson Elementary School, Cardoza said, adding that the district did take up one offer for books on safety, also for Sandra's classmates.