(NewsNation) — There’s a new development in a missing case that dates back more than 50 years.

A Texas toddler, named Melissa Highsmith, is believed to have been kidnapped by her babysitter in 1971. Now, someone claims to have seen her in Charleston, South Carolina, 1,000 miles from where she was taken.

The anonymous tipster said that a person resembles the age-progression photo released by the National Center for Missing & Exploited Children.

Melissa’s brother, Jeff Highsmith, told NewsNation he first heard about the development on Facebook.

“We believe she’s still alive. And obviously, somebody else does too in South Carolina,” Jeff said during a Tuesday appearance on “NewsNation Prime.”

Jeff and his wife Rachel have been actively searching for Melissa via podcasts and TV interviews. They’re hopeful that people will continue to share any coverage relating to her.

On Aug. 23, 1971, Melissa was just 21 months old when she was abducted by someone claiming to be a babysitter, according to NCEC. Melissa’s mother, who was recently separated, had placed an ad in a newspaper in Fort Worth, Texas, looking for someone to care for her child.

Someone picked up the toddler, who was in the care of her mother’s roommate at the time. The roommate said the woman who picked up Melissa “seemed nice” and was “dressed to impress, wearing white gloves.”

“It’s always been what I feel my life’s goal, to find my sister… We want to bring Melissa home to my parents before they take their last breath. And I really believe we’re going to. I really believe that God’s gonna open the door and we’re gonna find her soon,” Jeff said.