'A Bad Childhood': Woman Reunited with Family 51 Years After Being Kidnapped as Toddler Speaks Out

Growing up, Melissa Highsmith says something always felt off.

She lived a sheltered childhood, which was different from the two brothers she grew up with.

And the relationship she had with the woman who claimed to be her mom was riddled with trouble and hardship, compelling her to run away at the age of 15.

Thirty-eight years later she learned why their relationship was so difficult. She wasn't actually her mother — or related to her at all.

"Me and my mom were never close," Melissa, 53, tells PEOPLE. "And the whole time I was there, it was a bad childhood."

"I wasn't allowed to go outside and play, or she always sheltered me," she says. "And she said the reason she sheltered me was because I was born at home and that I had brain damage."

This year, Melissa — who grew up as Melanie Miyoko, but has now decided to go by her birth name — learned that her real family had been searching for her for the last 51 years after she was kidnapped at 21 months old.

In 1971, Melissa's real mother, Alta Apantenco, put an ad in the local paper searching for a babysitter.

On Aug. 23, when Melissa was a toddler, she was abducted from her Fort Worth, Texas, home by a person who responded to the ad, posing as a babysitter.

Melissa now believes her abductor was the woman who went on to raise her, just 10 minutes away from where she was taken.

"It started to make sense — all of the stuff that I had wondered when I was little: 'Why is my mom like this? Why is she like this?'" Melissa recalls of her rocky upbringing.

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"I just thought she had two boys and she had me, and maybe she didn't want a little girl. Maybe she wished that I was born a boy, and I used to wonder, 'Why did she even have me if she didn't want me?'"

Melissa's biological father, 73-year-old Jeffrie Highsmith, took a 23andMe DNA test and received his results this month, where he found a connection between himself and one of Melissa's three children.

After realizing this, Jeffrie's children confirmed Melissa was the long-lost sister they spent their entire lives searching for. The siblings Melissa never knew, Rebecca, 48; Victoria, 47; Sharon, 45; and Jeff, 42, messaged her through Facebook to get into contact with their sister who they never gave up hope of finding.

At first, she couldn't believe what she was reading.

"They think I'm their sister," Melissa recalls thinking. "Oh, this is a scam."

Naturally, she questioned her entire upbringing — and asked the woman who raised her if she recognized the name Melissa Highsmith via Facebook messenger. The woman denied knowing the name, but then came up with an alternate response.

"That's when she said, 'I've been wanting to tell you something for many, many years,'" Melissa explains. "She told me that somebody sold me to her for $500 on the street."

Melissa says she doesn't buy that story. Melissa hasn't seen the woman since 2002, but after the shocking conversation, she says she immediately cut all social media ties with her and blocked her on Facebook.

"In my heart, I don't believe she bought me," she says. "I think she was the one that answered the ad and abducted me."

"Everything that I had known before the age of 15, before I left home, was a lie."

After learning five days ago she had a pair of loving parents and four devoted siblings who never gave up the arduous search for her, she's now looking ahead toward the future.

"It makes me feel very blessed," Melissa says. "There's a time for everything. It just wasn't my time, but now it is, and [God] made this all possible."

Melissa says that for her entire life, she believed her birthday was Feb. 2, but it is actually Nov. 6. Now she and her husband have decided that every Feb. 2, they will "celebrate the death of Melanie."

Although the missing person's case for Highsmith went cold shortly after she was kidnapped, the family says they plan to meet with Fort Worth police to discuss the possibility of pressing charges against the woman who they believe abducted her, despite the decades that have passed.