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52 years. I still have people now and then that remember me asking me whatever happened to my sister that I ever find out.

I told her a couple recently, I told them to spread the words but I still have to happen to her. Usually when we went for a walk we walked together.

I just, that one time I didn't feel like walking down the tracks because she wanted to go back to the pond that we hanged out and dig up a muskrat with the dog.

I didn't go with her. I know that she had got there. I saw it with the dog and dug the hole. So I saw a back track where she had walked.

And I guess when she came back from what she was doing, that's what she got in the ad. That day I didn't go.

On July 11, 1969, 15 year old Cynthia Constantine took her dog for a walk as she did every afternoon in the family's hometown of Oakdale, New York.

Cynthia loved to walk along the railroad tracks that ran along a busy highway and often explored the area with her brother. On this day Cynthia walked her dog alone, picking up cattails along the way.

But Cynthia never returned home and when the family dog came home without her, the family immediately knew that something was wrong.

Backtracking her steps, Cynthia's mother and brother found a pile of cattails that Cynthia had likely collected and dropped. And this is a spot that Cynthia has believed to have vanished from more than 53 years ago and has never been seen or heard from again.

I'm Marissa and from Wondery, this is Episode 356 of the Vanished, Cynthia Constantine's story.

It's hard to imagine losing a loved one, a wife, a husband, a child. For many, it's their biggest fear. I'm Marissa Jones, host of the Vanished.

A podcast that tells the stories of often overlooked and unsolved missing persons cases, in an effort to uncover the truth.

Listen to the Vanished on Amazon Music or wherever you get your podcasts.

Oakdale, New York is a centuries old town, a hamlet within the town of Islip that dates back to 100 years prior to the American Revolution.

The town sits on the southern edge of Long Island and has always relied upon fishing, boating, and other seaside industries throughout its long history.

In the 1960s, Oakdale was still in the post-war era of development, and much growth was seen in the area, which felt like more of a small town than the busyness of Long Island and the New York City metropolitan area.

In fact, in 1969, statistical records indicate that the New York City area had a population of 16 million people, whereas Oakdale had a population of about 7,300 residents,

which has remained nearly unchanged in the last 50 years.

It was in this environment that Cynthia Constantine and her family lived. Her parents owned a bicycle shop not far from their house, and she and her brother William grew up there.

So this many years later, William is the only family member who was still alive, and he continues to look for Cynthia at 70 years old, hoping to find her before no one else is left to look.

We spoke with William for this story after he reached out to us earlier this year, so we could help him tell his sister's story.

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