FAYETTE COUNTY, Ga. — A Fayette County teenager will spend the rest of his life behind bars after a 15-year-old girl was shot and killed in her bedroom.

Madison Gesswein was murdered on Feb. 21, 2023 at her apartment complex in Peachtree City. Her mother discovered her daughter’s body when she got home from an overnight shift.

Gesswein was a student at Whitewater High School in Fayetteville. Investigators later arrested Jacobean Brown and two other students Justus Smith and Yeshua Mathis on murder charges.

On Tuesday, the Fayette County District Attorney’s Office announced that a jury found Brown guilty in Gesswein’s death after a week-long trial.

Prosecutors said they showed the jurors text messages between the victim and the defendants, who were 18 at the time. Prosecutors said the three teens went to Gesswein’s apartment, where Brown snuck in through her bedroom window.

Brown shot the 15-year-old in the head while she was lying on her bed, according to the DA’s office. Investigators found a 9 mm pistol with an extended magazine and cleaning supplies at the scene.

A judge sentenced Brown to life in prison without parole plus six years.

“Violence by young people is a growing concern across the State,” Fayette County District Attorney Maria Broder said. “My office is committed to the fight against violence in our communities, no matter the age of the offender. I am grateful to my team and our law enforcement partners for their work on this case, and to the jury for their pursuit of the truth and justice for the victim.”

Court records show a September trial date has been set for Smith and Mathis.