Yanas Tigan
Yanas Tigan was an unjoined Trill in the 24th century that lived on Sappora VII near New Sydney. She and her husband were the parents of Janel, Ezri, and Norvo Tigan.

Family
Yanas did not have a good relationship with her children, especially Ezri, her only daughter. This was due to Yanas' stern, authoritarian nature coupled with her domineering behavior. This relationship deteriorated even further when Ezri was joined with the Dax symbiont. Carrying the memories of Dax's eight previous hosts, Ezri found it difficult to distinguish herself from the others. When Yanas came to visit Ezri on  after being joined, Ezri presented herself to her as Curzon. This convinced Yanas that Ezri should come home, and when she didn't, Ezri noted that "things went downhill from there." () 

Soon after, Ezri took a leave of absence to visit Benjamin Sisko less than three months after Jadzia's death, sharing with him: "My parents, my friends, my crewmates, it's like they don't even know me anymore." ()

Yanas encouraged her youngest son, Norvo, to work for the family business despite his interest in the arts after he was not accepted into the Andorian Academy. Her criticism wore away at his confidence until he was repeating her critiques.

Business
In 2375, she was one of the "more important business leaders" in the Sappora system, owning the sixth largest pergium mine in the Sappora system, where her sons Norvo and Janel worked for her and lived with her. As the ultimate authority over payroll, she transitioned many day-to-day operations to Janel. 

During a tough time that threatened the company, unbeknownst to Yanas, her two sons had gotten involved with the Orion Syndicate to protect the company from bankruptcy. When Starfleet Chief Miles O'Brien went missing, Yanas' daughter Ezri visited to solve the situation, finding Chief O'Brien, and determining that her brother Norvo had killed a Morica Bilby.  Yanas realized that she was to blame. ()

Background
Yanas Tigan was played by Leigh Taylor-Young. Her first name comes from the script. First draft production materials, dated October 9, 1998, list her name as "Yana Tiyan." 

The script describes Yanas as "a lean and regal-looking Trill woman in her late fifties. She wears a tastefully tailored casual suit. She's beautiful, and radiates the iron resolve of a self-made woman."

StarTrek.com's biography of Ezri suggests Yanas may have held resentment towards her serving in Starfleet. 

According to the novella Saturn's Children, the mirror universe counterparts of Yanas and Janel were murdered by the Klingon-Cardassian Alliance in 2375 for helping more than three hundred  slaves escape from New Sydney and Sappora VII. They were turned in by Norvo, who received a full pardon.

External link
 

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Trill