The note said the bottle had been buried on the beach with the help of the siblings' father March 3, 2000.
Grace sent a photo of the letter to her children and was shocked to read the response from her son, Michael.
"Michael's like, 'You're not going to effing believe this, but Roman and I went to college, and we both worked at DHL,'" Grace told WINK-TV. "'And here's a picture of us out in California with DHL last year on the beach.'"
Grace said the revelation gave her "goosebumps."
"We're like, how could it be? All of the millions of people that have been on board this beach since this was buried, and I find it and within minutes we know who it was," she said.
Grace was recently able to contact the Mural siblings and tell them about her discovery and their surprising connection.
"It just proves that the world isn't that big," Lesia Mural said. "And we're all in connection, have one or two connections away from a lot of people."
Lesia Mural wrote on Facebook that the incident evoked the song "It's a Small World."
The siblings said the discovery brought back memories.
"Fort Myers is always a place that we used to go down for many years and still do today," Roman Mural said. "Just to be able to have that bottle come back to us and then recreate some of those Fort Myers memories, that truly was a bright spot in my day and kind of cutting into the holiday season. Kind of want to go back now home and watch that home video again."
Gregory D'Alessio of Alexandria, Va., was fishing near Maryland's Solomons Island one day before Grace's discovery when he found a message in a bottle bobbing in the water.
The bottle turned out to contain an obituary and several small, rolled-up notes. The obituary was for Maryland woman Emma Jean Ennis, who died at the age of 82 in January 2021.