The relatives of Donna and Richard Muller appealed to the neighborhood of Lawncrest, the parish of St. William's and the city of Philadelphia.
They're looking for an executioner.
"I am begging this community that has experienced so many acts of tragedy and violence in recent months to come together and push back against this violence," said Heather Muller Kunf, Donna's daughter and Richard's sister.
On Wednesday, inside the Church of St. William on the 6000 block of Rising Sun Avenue, the Muller family spoke publicly for the first time regarding the "Execution-style" murder of the mother and her son on Jan. 19. Donna, 49, and her 22-year-old son, Richard, were found dead on the second floor of their Northeast Philadelphia row home on the 300 block of Stevens Street with gunshot wounds to the back of the head.
Despite various leads and tips, the Philadelphia Police department is no closer to finding the murderer.
"No good leads right now," said Capt. James Clark. "We've gotten several tips but I'm letting the public know we need more because a lot of them have fizzled out."
There was no sign of forced entry. Nothing was stolen and the house wasn't ransacked. The dog didn't bark.
"We don't have motive," Clark said. "But we feel like someone knows who did this double murder."
Clark said police still aren't sure whether this incident was related to the triple homicide in Lawncrest in February, in which three people were also killed in the same execution-style. He added that he isn't sure if this is a case of mistaken identity.
At the church, which is a few blocks away from the Muller's home, Catherine Rohland, sister and aunt of the deceased, said both Donna and Richard were born and raised in Lawncrest. Both attended Cardinal Doughery High School.
"Our family has deep roots in this community," Rohland said. "We do not know why someone chose to murder them. What is certain is that Richard and Donna Muller should not be dead."
Muller Kunf added: "I can't sleep at night knowing that whoever did this — the person or persons — that they're still out there and I don't feel safe.
"The community shouldn't feel safe knowing that the person wasn't caught."
The city is offering a $40,000 reward — $20,000 per victim — for information that leads to the arrest and conviction of the murderer.
Anyone with information is asked to call the police tip line at 215-686-8477, or text a tip to PPDTIP (773847). The Homicide Unit can also be contacted directly at 215-686-3335.
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