List of unnamed Betazoids.
A week prior to Julian Bashir's and Jadzia Dax's meeting at Quark's, a Betazoid envoy visited Deep Space 9. Dax reminded Bashir about his interest in the envoy but Bashir answered that she was a barely adequat substitute for Dax. (DS9: "If Wishes Were Horses")
There were several members of Lwaxana Troi's family, including her parents and a sister, who had died prior to 2373. That year, she confessed to Odo that the loss of her family, as well as a husband, and especially the loss of her daughter Kestra had made her depressed. (DS9: "The Muse")
Lwaxana's father, who was Deanna Troi's grandfather, was someone Troi spent time with on Betazed while growing up. He was a man who rarely spoke, noting that talking was for off-worlders and people who didn't know any better.
When Troi got older, the only time she could remember his stories was when she went home to Betazed and sat by the fireplace, adding that at times, when she was alone there, it was almost like she could hear his voice inside her head. (TNG: "Eye of the Beholder")