Crystal Shroyer, 32, was arrested after allegedly sleeping with the underage youngster.
The boy came over during a party after fleeing his parent's house in Connellsville, Pennsylvania, according to court documents.
The alleged teen victim was dating Shroyer's daughter last year until she died in June, police said.
She has now been charged with statutory sexual assault and corruption of minors and she is being held on £6,500 bail.
Police said: "Sometime in early March, the victim stayed at Shroyer's residence after he ran away from his parent's house.
"Shroyer was hosting a party on this particular evening in early March and after interviewing Shroyer, she admitted to having sexual intercourse with the victim."
She will face a preliminary hearing on the 15th of June.It is not known what caused the death of Shroyer's daughter or how old she was.
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