Betsy Bailey shared her childhood with a younger sister, gliding across a frozen pond behind their home in Chappaqua, N.Y., and later moving to Sherborn, where the girls explored trails on horseback.
But Bailey’s memories of her sister, Simone Ridinger, end in September 1977. That’s when Ridinger, then 17, disappeared after finishing her shift at a Natick restaurant where she was a waitress. In honor of Ridinger’s 60th birthday on Sunday, the National Center for Missing and Exploited Children and Sherborn police are renewing their push to solve the mystery of her disappearance nearly 43 years ago.
“They have told me that they don’t ever give up as long as someone is missing,” Bailey, 62, said Saturday in a phone interview. “We won’t ever forget her.”
In a blog post published Thursday, the missing children’s organization provided details about Ridinger’s disappearance. The group also posted a video about the case and a forensic artist produced an image of what Ridinger may look like at age 59.
The mystery began on Sept. 2, 1977. After leaving work, Ridinger was expected to go to Chappaquiddick Island where her mother, Jane Barrett, was staying at a family cottage. But Ridinger never showed.
An FBI alert said Ridinger was last seen wearing blue jeans with rips and patches, white high top sneakers, and silver jewelry. She accessorized with “spoon rings,” bracelets, and turquoise stones and had strawberry-blonde hair, the FBI said.
Ridinger was carrying a gray duffel bag containing her waitress uniform of a dark blue polyester skirt and vest top, the FBI said.
Sherborn police Detective James Godinho, who took over the investigation in 2014, was quoted by the missing children’s group in the post as saying Ridinger was known to hitchhike.
“She hitchhiked everywhere. To and from work, to and from school,” Godinho said in the post. “However, when she was discussing her plans to hitchhike to Cape Cod with her coworkers and family, there was a little bit of concern – even though the practice was prevalent back then – because of the distance involved.”
Initially, Ridinger’s relatives weren’t alarmed when she didn’t show at the cottage, the post said. She was a free spirit and had a reputation for running late. Further, her family had limited communication on the island because the cottage didn’t have electricity or a phone, according to Bailey.
But when Barrett left Chappaquiddick and learned no one had heard from Ridinger in more than a week, the family began its search, Bailey said.
Relatives distributed fliers featuring Ridinger’s photos and called her friends. Her father, John Ridinger, belonged to a citizens band radio club and the group searched Cape Cod, Bailey said.
In 1986, a man came forward saying that he may have given Ridinger a lift to Cape Cod the weekend she went missing, the post said.
He learned about the case, the post said, from a newspaper story featuring photos of Ridinger and believed she had been the girl in his car. The man told a story about being pulled over by a state trooper while driving to Osterville on Route 128 on the same day Ridinger was last seen at work.
In the trooper’s car was a teenage girl who was headed to Cape Cod, the post said. When the trooper learned the man was also headed to the Cape, he asked him to give the girl a ride.
The man agreed, the post said, and dropped off the girl off at a Rotary Club near the airport in Barnstable. His description of the teenager and the clothing she was wearing matched accounts from two former restaurant colleagues who described Ridinger’s appearance on the day she was last seen.
The man has since died, Bailey said.
Anyone with information about Ridinger is asked to call Sherborn police at 508-653-2424 or the National Center for Missing and Exploited Children at 1-800-THE-LOST.
On Saturday, Bailey recalled going riding with her sister on horses named Penuche and Chocolate Sundae. Ridinger rode Chocolate Sundae, Bailey said, who was smaller and got her name because she looked like vanilla ice cream topped with chocolate sauce.
Bailey said she keeps Ridinger’s memory alive by telling her children about the aunt they never met.
“I think she’d get a kick out of her niece and nephew,” she said. “She just wanted to have fun.”
Bailey also said she is comforted by the continued efforts to learn what happened to Ridinger.
“Just knowing someone is doing something is helpful,” she said. “You miss her every day, always.”
Laura Crimaldi can be reached at laura.crimaldi@globe.com. Follow her on Twitter @lauracrimaldi.