Detectives visited the North Philadelphia rowhouse of Sharon Hopkins last Tuesday to deliver terrible news: Her 20-year-old granddaughter, Tiyaniah Hopkins, had been killed in an execution-style quadruple homicide in West Philadelphia.

A day later, the news got worse. While visiting the morgue, Hopkins learned that Tiyaniah's sister Yaleah Hall, 17, also was among the victims.

Hopkins, 61, said Monday that her granddaughters were an important part of her family's life, and that they all were devastated by the deaths. When detectives explained the purpose of their visit, she recalled, "I just started hollering and hollering, 'No! No!'"

Police on Monday publicly identified Hopkins and Hall as two victims in the killings. The others, police said, were William Maurice Taylor, 31, and Akeen Mattox, 28. The men, who considered themselves stepbrothers and were raised together, had recently moved into the house on the 5100 block of Malcolm Street where they, Hopkins, and Hall were found dead on Nov. 19 in the basement.

Homicide Lt. Norman Davenport said that investigators were still working to identify suspects and a motive. Because the killings occurred inside a house and without any surviving witnesses, he said, it can be a "long process" for detectives to analyze physical evidence, contact those who spoke to the victims before they were killed, or sort through whether anything in the victims' backgrounds offers clues.

He encouraged anyone with information to speak to detectives, noting that an $80,000 reward is being offered for information leading to a conviction in this case.

Hopkins and her husband, James, 69, said one rumored motive is that Taylor or Mattox were targeted over a belief that they had money, or were set up for a robbery. Another is that the unidentified killers had a problem with Taylor or Mattox, but killed everyone at the home to eliminate witnesses.

Davenport said it was possible that the women, who did not live in the house, were killed simply because they were there.

James Hopkins said that whatever the reason, "four souls were taken out of here and shouldn't have been taken."

He said he and his wife raised the two girls from infancy until Tiyaniah was about 9, when the girls moved back with their parents. Sharon Hopkins said the sisters — who had four other siblings — were cheerful and intelligent, and loved to dance.

"They were full of life," Sharon Hopkins said.

She said she recalled tossing her phone in disbelief when detectives told her Tiyaniah had been killed. She couldn't bear to see her granddaughters' bodies in the morgue.

Sharon Hopkins said she did not know Mattox or Taylor, and said her relatives didn't either.

She and her husband hope police quickly identify whoever pulled the trigger. James Hopkins said they are trying to find the right way to cope with their grief, but that it is difficult.

"When you put time in with someone," he said, "you don't just erase it off."