A woman who was abducted when she was a baby has been reunited with her family 51 years later.

Melissa Highsmith went missing in 1971 when, at just 22 months old, she was taken by a babysitter from her parents’ Fort Worth, Texas, home.

Melissa’s mother Alta Apantenco was working as a waitress and in need of a babysitter so she put an advertisement in the newspaper.

Ms Apantenco hired a woman who expressed interest in the job without meeting her in person.

While she was at work, her roommate handed Melissa over to a babysitter who allegedly abducted her and never returned.

According to the family, Ms Apantenco faced years of accusations from investigators that she had possibly killed her daughter and hidden the crime.

But the family never gave up in their search for Melissa and in recent years they created a Facebook page named Finding Melissa.

But the breakthrough came when they used the websites Ancestry and 23AndMe after taking advice from a genealogist.

“Every time my mother got her hopes up. After 51 years, she didn’t want to submit another DNA test. She was tired and she was hurt and guilty from carrying this all these years,” said Victoria Highsmith, Melissa’s sister.

“I’m thankful that we got her to agree to submit her DNA … It is because of that, and my dad submitting, that we were able to find Melissa.”

Victoria said they didn’t find Melissa through her own DNA sample but through her children’s DNA and that the match came back quickly after both of her parents submitted their samples.

“Within three weeks we found my sister. It was like, ‘Boom, boom, boom’, we found her,” said Victoria.

Melissa, now 53, has been living in Fort Worth for most of her life and never knew she had been kidnapped, her family wrote in posts on a Facebook page named We Found Melissa!!!

On Saturday, during a celebration at a church, Melissa was reunited with her mother, her father Jeffrie Highsmith and two of her four siblings.

“I couldn’t stop crying. I was overjoyed and I’m still walking around in a fog trying to comprehend that my sister is right in front of me and that we found her,” said Victoria.

“It’s a Christmas miracle! It’s amazing meeting her. It was like looking into myself, she looks like me, like us. She’s overjoyed to be in our lives.”