(NewsNation) — At a pre-trial hearing last week, a judge decided a controversial “burn after reading” letter can be considered evidence in the civil trial between the parents of Gabby Petito and Brian Laundrie.

Petito family attorney Pat Reilly told “NewsNation Prime” he was “shocked by the language in the letter” when he first read it last year in Tampa’s FBI office.

Reilly sent pictures of the letter to NewsNation senior correspondent Brian Entin last week. Part of the letter from Roberta Laundrie to her son says: “burn after reading.”

Another portion reads: “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.”

Gabby’s mother, Nichole Schmidt, and father, Joseph Petito, filed a civil lawsuit last year against Chris and Roberta Laundrie. Gabby’s parents insist the Laundrie’s knew about their daughter’s death before her remains were discovered and helped their son flee justice.

Roberta Laundrie sent Entin a statement about the letter. It reads in part: “I am sure people use phrases all the time to express to their loved ones the depths of their love. Although I chose words that I thought would be impactful with Brian given our relationship, the letter was in no way related to Gabby.”

Laundrie claims the letter was written before Gabby and Brian left for their trip. Reilly said if that’s the case, “it’s very ironic.”

“To take the position that the letter was written as a love letter to a son or a letter to a son to express how much you love him, there was an odd choice of words there,” Reilly said.

Reilly pointed out that while the letter is undated, he doesn’t know that criminal charges could be brought for it.

“I don’t know what criminal charges there could be. Because I don’t think there was anyone acting to help bury the body. There’s just an expression of, a willingness to commit a crime,” Reilly said. “There’s no indication that willingness was ever acted upon.”

Reilly wants the focus to remain on the civil suit.

“The purpose of the letter for the civil proceeding the Petito family has brought against the Laundrie family is that it shows they were aware that Gabby was deceased at the time their attorney on Sept. 14 made a statement that he hoped that Gabby Petito would be reunited with her family,” Reilly said.

He continued: “While the inference there is they had to have known that she was deceased, this letter just adds another layer to that and shows how callous their statement was on Sept. 14.”

Due to a long list of pre-trial hearings, the civil trial between the families has been rescheduled for May 13, 2024.

NewsNation digital content producer Liz Jassin contributed to this report.