The mother of a man who killed his girlfriend on a cross-country trip in an infamous murder case wrote him a letter offering to help him “dispose of a body,” according to reports.

It’s the latest revelation in the case of Brian Laundrie, who killed himself at some point after receiving the letter. Police say Laundrie killed Gabby Petito in 2021 while the couple was trekking across the country in a conversion van, publishing blissful romantic videos of their travels. Her body was found in Wyoming.

“If you’re in jail, I will bake a cake with a file in it. If you need to dispose of a body, I will show up with a shovel and garbage bags,” Roberta Laundrie wrote in a letter she instructed her son to destroy after reading.

The letter, which CNN obtained and published photos of, was undated and contained in an envelope that said Laundrie’s name and “(burn after reading).”

“I just want you to remember I will always Love you and I know you will always Love me. You are my boy,” the letter reads.

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Petito’s disappearance that summer gained national attention, with weeks of speculation about what happened to her and whether Laundrie, her fiancé, had killed her. Laundrie returned from the trip without her, and her family reported her missing. Laundrie later also disappeared.

The case drew attention to domestic violence, and police footage showed officers in Utah speaking to the couple after they were pulled over in a traffic stop. They said they had been fighting and police ultimately let them leave. A review found Moab police made mistakes and missed signs of domestic violence, and Petito’s family filed a wrongful death lawsuit against the police.

Petito’s body was found in Grand Teton National Park in Wyoming in September 2021, and a coroner ruled her death homicide by strangulation.

Laundrie admitted to killing her in writings found with his body at Carlton Reserve, nearly 25,000 acres of land in southern Sarasota County in Florida, in October 2021, authorities said.