Rescuers were called around 4:00 p.m. to her home in the 900 block of Decoys Way, in the Hunter's Glen trailer park.
The gruesome discovery was made by the Leifheit's great aunt, who is also her guardian, when she got home from work.
"I heard someone screaming when I was inside, and I wasn't sure. I thought it was the kids outside playing," said neighbor Chad Mason.
Relatives say Leifheit was discovered in her bedroom.
Paramedics say when they arrived, she was in cardiac arrest and died moments later from what appears to be multiple stab wounds.
Police have taken Destiny Leifheit's ex-boyfriend and some of her friends in for questioning.
So far, no one has been ruled as a suspect or accomplice.
Meanwhile, residents have been left shaken by the gruesome murder of the middle school student.
"It's so quiet here... sometimes our doors aren't locked," said neighbor Francis Kuhn. "Now they're going to be locked."
Police at this point do not believe this was a random act of violence, but they have not yet zeroed in on a suspect.
However, there has been some intense grilling of some of those being questioned.
If you know anything that may help investigators, you're asked to call:
New Castle County Detectives at (302) 395-8110
Crime Stoppers at (800) TIP-3333
or, visit the New Castle County Detective's website.