An 11-year-old Northeast Philadelphia girl died from what appears to have been natural causes while at a neighbor's house Wednesday for a sleepover, police said Thursday.

The Medical Examiner's Office ruled that the death was not the result of trauma or foul play, said Lt. Dennis Rosenbaum of Northeast Detectives.

Police did not release the girl's name.

The preliminary finding by the Medical Examiner's Office was that the death was natural and resulted from something that had not yet been determined, Rosenbaum said. The office will await the results of neuropathology and toxicology tests, which could take from six to 12 weeks, before determining the official cause of death, Rosenbaum said.

The girl was staying at the home of a 15-year-old friend, who lived two doors away on the 9200 block of Angus Place, Rosenbaum said.

Also in the home at the time were the friend's three younger sisters, a brother, and parents.

The girl was found unresponsive by one of the younger sisters about 10:15 a.m. Wednesday, Rosenbaum said. The girl was taken to Jefferson Torresdale Hospital, where she was pronounced dead at 11:20 a.m., police said.

"It's a sad story," Rosenbaum said. "It's hard for all of us to investigate."

Police are no longer investigating the death because it was deemed not to be criminal, he said.