A 41-year-old man was sentenced to 12 years in prison after impregnating and pleading guilty to the forcible rape of his girlfriend’s 15-year-old daughter, the 21st Judicial District Attorney’s Office announced Friday.

In July 2013, the victim’s grandmother found out the girl was eight months pregnant and called law enforcement, the District Attorney’s Office wrote in a news release. She said her granddaughter became pregnant while living in Hammond with her mother and her mother’s boyfriend, Brian Hoyt, of Indianapolis, who is HIV-positive.

Police tracked down the family, who had moved out of state, but the victim did not identify the father of her child. However, officials collected a sample of Hoyt’s DNA and, when the victim gave birth to a baby girl, performed a paternity test, which showed he was the father, the release says.

“The victim told authorities that she could not disclose the father of her child at first because her mother and Hoyt made threats that they would make her give the baby away and other similar threats,” the release states.

The teenager and her daughter were both tested to determine whether they also are HIV-positive, but the District Attorney’s Office has not been informed of the results of those tests, spokeswoman Autumn Payton said Friday.

District Judge Elizabeth Wolfe handed down the 12-year sentence, which is to be served without the benefit of probation, parole or suspension of sentence.