WhenLeticia “Leti” Martinez-CosmaninvitedBrett Gitchelon a date to attend the Seattle Mariners baseball game at T-Mobile Park on March 31, she had no idea she would never see her family again.

As a single mother and the primary caregiver to an adult son with special needs, Leticia, 58, rarely had a night out. But as a die-hard Mariners fan, she allowed herself time to decompress at the ballpark during baseball season.

After meeting Gitchel, 46, at a warehouse store food court a few weeks prior to their get-together, the pair bonded over their mutual love of the Mariners, and Leticia offered to take him to the next game.

Leticia Martinez-Cosman.Ricardo Martinez

Leticia Martinez-Cosman

“She noticed he was wearing a Mariners hat, and one thing led to another,” Leticia’s brother Ricardo Martinez, 53, who spoke with her shortly before the game, tells PEOPLE. “She hadn’t been out in a while, so she says, ‘OK, let’s just see how this goes.'”

Leticia snapped a selfie of herself and Gitchel at the game, documenting their time spent together, but she never made it home that night. Ricardo reported her missing April 2.

Leticia Martinez-Cosman, Brett Gitchel.Seattle Police Department

Leticia Martinez-Cosman and Brett Michael Gitchel at the Mariners game before she vanished on March 31, 2023

An investigation revealed Gitchel allegedly kidnapped Leticia’s son, Patrick Cosman, from the family’s West Seattle home hours before her reported disappearance, according to the King County Prosecuting Attorney’s office. Gitchel drove Patrick to a remote area in Renton, Wash., where he allegedly attempted to strangle and murder him before Patrick, 24, managed to escape and call for help.

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Nearly two weeks later, her remains were located in a ditch in Renton. She had been strangled to death, say authorities.

Brett Gitchel.Department of Corrections

Brett Michael Gitchel charged with the murder of Leticia Martinez-Cosman

Gitchel was arrested April 5 and charged with murdering Leticia. He pleaded not guilty to attempted murder and kidnapping in Patrick’s case, and pleaded not guilty to murdering Leticia.

“My sister was a very giving, trusting person. She always looked out for the best in anyone,” says Ricardo. “I think this low-life thief targeted her. I guess he saw, ‘Oh, she’s got baseball tickets. I wonder if she’s got money.’ And when Leti somehow got in his way, he just killed her and tried to kill her son to cover his tracks.”

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In Seattle, she met her best friend, Annie. “She’s just very fun-loving, sweet and kind,” remembers Annie, 55. “The most generous person you could ever meet.”

Since his mother’s death, Patrick has moved to Texas to live with his father. But Ricardo remains in Seattle where he continues his fight for justice on behalf of his late sister.

“I’d like for him [Patrick] to be happy and everyone never forget who she [Leticia] was,” says Ricardo. “That would be my justice.”

source: people.com