SPRINGFIELD, Mo. -- The Greene County sheriff says people with information about a brutal double homicide are refusing to talk. Sheriff Jim Arnott says they are ignoring pleas to “do the right thing” and help solve the murder of Don and Helen Willingham.

On April 25, someone stabbed the couple to death in their home south of Springfield. Their family members say they need help to catch their killer. “They are still out there that's the scary part for the whole community,” the couple’s son David Willingham said. “You've got to wonder where they are, what they are doing and who is next.”

The person who killed David Willingham's parents is free and has been for four months. “There was no reason for them to target my parents,” Willingham said. “It could be just as random for somebody else.”


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Two persons of interest are in custody facing unrelated charges but that doesn't bring comfort to the Willingham's son. “I don't know who they are, what they've done or anything,” Willingham said.

The Greene County sheriff says a group of people are not talking to deputies because they fear retaliation for working with investigators. “I ask I beg whatever motivates you whether it is your conscience or money that you come forward and do the right thing,” Arnott said at a July news conference.

Last month’s plea for information fell on deaf ears. “They’ve talked to some people and then people get cold feet,” Willingham said. “We've been hopeful a few times to have our hopes dashed.”

The family says the information is vital, critical. They're offering a $20,000 reward for credible information that leads to arrests and criminal charges. “We really, really need that information,” Willingham said. “Clear your conscience, get reward money and more importantly do the right thing. Please, please call the sheriff's office.”

The sheriff says 519 pieces of evidence were gathered by investigators. Eighty-four pieces of evidence have been sent to the Missouri State Highway Patrol's crime lab for further analysis.

Anyone with information can call the sheriff's office at 417-868-4040 or anonymously report a tip to Crime Stoppers at 417-869-TIPS (8477).