The two suspects in this case, 42-year-old Kelvin Roberts of Philadelphia and 41-year-old Charles Fulforth of Jenkintown, are both now charged with first-degree murder.
"They went to the house with bad intentions and shot an innocent 61-year-old woman as she lay in her bed, and they executed her 25-year-old son," said Montgomery County District Attorney Kevin Steele.
Steele noted that he used the word "executed" because the son, Andrew Gaudio, was shot in the back of the head as he was on the floor of his mother's bedroom.
"He was face down when the shot to the back of the head came," Steele said.
His mother, Bernadette, was sleeping in her bed when one of the suspects entered and shot her. She survived and managed to call police.
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Steele said the two suspects worked at Junkluggers, a junk removal business, in Willow Grove.
On Dec. 6, Junkluggers employees did an estimate at a house in Bucks County with a similar address to the victims' home in Lower Merion Twp., Montgomery County.
Following that estimate, information was given to Fulforth, and then Roberts, about "a whole lot of guns" being in the Bucks County house, Steele said.
"Seemingly what got lost in translation is where the intended house was," Steele said. "It was simply the wrong house."
News conference on Lower Merion Twp. home invasion
The shooting happened around 2:20 a.m. on Sunday, Dec. 8 inside a home on Meredith Road.
Roberts was arrested at Junkluggers on Tuesday morning. Fulforth was arrested last week.
Steele said they want to know if anyone who got an estimate or hired Junkluggers had items stolen or had their homes burglarized.
Investigators also want know who told the suspects about the house with the guns in Bucks County.
"There was someone within the business that was feeding them information, and our investigation is ongoing," Steele said.
He also said the suspects are "clearly" involved in gun trafficking, noting that a 3D printer and indications of a "ghost gun" were found.
Anyone with information should contact the Montgomery County District Attorney's Office.