Genealogy and DNA technology has once again solved a decades-long cold case, this time in Indiana.

John D. Miller pleaded guilty Friday to the 1988 abduction, molestation and murder of 8-year-old April Marie Tinsley in Fort Wayne, WISH-TV reports.

Tinsley, who was in first grade at the time, disappeared after walking to a friend’s house to get an umbrella. Three days later, a jogger discovered the girl’s body in a ditch. Investigators determined that she had been raped and suffocated, and had been dead for at least 48 hours.

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As CrimeOnline previously reported, investigators eventually matched Miller’s DNA to the crime years later, as well as the taunting messages left behind. The first cryptic message appeared two years after April’s death, when the killer scrawled, “I kill 8 year old April Marie Tisley I will kill agin [sic],” in crayon on a barn door, close to the area where April’s body was found.

Around 14 years later, the killer began pinning notes in several places, including inside baggies with used condoms and on girls’ bicycles left in their yards. The suspect also allegedly left behind Polaroid photos of April’s body in baggies. The DNA found in the used condoms matched the DNA found inside April’s underwear, according to authorities.

“Hi Honey I Been watching you I am the same person that kinapped an Rape an kill Aproil Tinsely. You are my next vitem [sic].”

In May, Parabon NanoLabs matched the DNA the killer left behind to genealogy data, which narrowed the killer to either Miller or his brother. Police conducted surveillance on Miller’s trailer and took items containing his DNA from the trash. There was a match.

Miller did not take long to confess, according to court documents. When authorities asked why he was there, he responded: “April Tinsley.”

Prosecutors subsequently charged Miller with murder and child molestation. The case had been headed to trial in February, but the guilty plea means he will now be sentenced December 31.

Under the plea deal, he’ll serve 80 years in prison: 50 for the murder and 30 for the molestation. A judge must still sign off on the sentence.

Earlier this year, similar genealogy and DNA technology helped nab the Golden State Killer, a man accused of killing a Canadian couple in 1987, and a suspect in the 1986 rape and murder of a 12-year-old girl from Tacoma, Washington.

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[Feature Photo: April Tinsley/FBI]

*Editor’s Note*: Additional reporting provided by Leigh Egan.