Homicide Capt. James Clark said during a news conference yesterday that Muller and her son were both found shot in the back of the head, execution-style, on the second floor of the property. There were no signs of forced entry, no signs the place had been ransacked.
Clark said investigators believe that the crime was personal, that the killer or killers knew Muller, who worked as a senior editor at Reed Technology in Horsham, or her son. The family's dog did not attack or bark during the double slaying, which appears to have unfolded between 10:30 a.m. and 3 p.m. Sunday.
Clark asked tipsters to call the Homicide Unit at 215-686-3334 or -3335.
As of Sunday night, the city had recorded 22 homicides - twice the number recorded at the same time last year - including six over the weekend.
Frank DeFranco, who lives at the end of the Mullers' block, said he would often see Donna walking her dog.
"I feel bad for the family," he said. "I just think, 'Who would do something like that?' "
"She was a good neighbor," said another resident, who didn't want to be named. "But I complained in the past . . . they had a lot of traffic, a lot of activity, in the back alley behind their house."
Rich Muller's friends said he recently graduated from Manor College in Jenkintown and tended to keep to himself. He also worked part time in the kitchen at the Holy Redeemer Lafayette retirement community.
"As an employee of Holy Redeemer, Richard ascribed to our mission to care, comfort, and heal, and his loss has shaken our staff deeply," Holy Redeemer said in a statement yesterday. "Our condolences and prayers go out to Richard's family."
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