(CBS NEWS) -- Nearly a month after losing her 16-year-old daughter in a car crash, Cindy Mathis found something that gave her the comfort she desperately needed: a letter — a bunch of them, actually.

The mother had almost forgotten about the 25 notes her daughter, Macy, gave her on her birthday last year.

“Open when... you miss me,” one of the envelopes read. Each letter followed a similar pattern, instructing the mom from Tifton, Georgia, to open a note when she was feeling lonely, restless, excited — you name the emotion, there was a message.

“They’re so on point, and there are occasions where she knew me way too well,” Mathis told CBS News. “My daughter knew me.”

Some letters have made her laugh, others made her cry, but she’s thankful to get a piece of her daughter back, even if it’s only through words on a page.

“Most of them are definitely definitely uplifting,” Mathis said.

Macy died on Nov. 25, five days after she got into a car crash while riding with her 18-year-old boyfriend, Adam Sattler. He was also killed in the wreck.

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