It began as a mystery in the mailbox — a letter originally postmarked in 1967 and labeled “Return To Sender.”

Within hours, it evolved into an emotional tale of history and heartache for one Atlanta family and a stranger whose lives, they discovered, are intertwined.

Tene Tucker returned home on a recent Sunday from a 10-day vacation and began the usual ritual of sifting through mail that had piled up. It was mostly bills and junk mail. But something else caught her eye.

“I found this letter toward the bottom of the stack and just looked at it,” Tucker said, “and was, like, ‘What is this?’ ”

The small white envelope had been sent from her address on 3rd Avenue in Scottdale, Ga. It was originally postmarked Aug. 15, 1967, according to the black stamp at the top of the envelope. “Return To Sender” had been scribbled on the front.

First, Tucker said, she “just kind of stared at it for a while.” After opening the 52-year-old letter, she began putting together the pieces of the puzzle to reunite the letter with the person who penned it.

The letter was written by a woman named Betty Hayes, who mailed it to a man named Marvin Armstead in 1967. Armstead appears to have been stationed at McGuire Air Force Base in Burlington County, N. J.

“Hi son. How are you? I got your letter and was glad to get it,” Hayes wrote, before giving updates on her life. She concluded the letter by writing, “Remember, no one can be more proud of one little boy. From Betty to my son, with love.”

Touched by the letter, Tucker wrote a post about it on social media. She felt an obligation to find Hayes’ family.

Less than 24 hours later, Mary Hayes happened to be watching TV with her mother when a Channel 2 Action News story about the letter aired.

“It said the address, and then [named] my mom,” said Mary Hayes, who lives in a southeast suburb of Atlanta. “I was very surprised.”

Her brother, Sylvester, also saw the report. Immediately, they all went to Tucker’s house, where they had grown up. Tucker was able to personally hand the letter to Betty Hayes, who is now 84 and was the first owner of the house. She suffers from Alzheimer’s disease, but appeared to recognize the modest, single-story home, originally built in 1940.

“I’m just excited the letter came back and we were able to really read it,” said Mary Hayes. “It was very emotional, it really was.”

Tucker also learned heart-rending details about Armstead, the letter’s intended recipient. He is Hayes’ biological nephew, but his mother died when he was 3 years old, so Hayes raised him like her own son. After leaving home at 16 to serve in the U. S. Air Force, he worked in the DeKalb County School District, received a master’s degree and was a professor.

But Armstead, who is now about 70, also has dementia, and his family has not seen him for about 10 years, Mary Hayes said.

“We’ve been really trying to find him,” she said. They think he is still alive and in the Atlanta area, since they believe he sometimes visits local Department of Veterans Affairs hospitals.

A private investigator who contacted Tucker has agreed to help.

“Wherever Marvin is, he has a good family that loves him and misses him, and they’d love to find him,” she said.

“The story doesn’t end here.”