I've been watching Wrongs Darker Than Death Or Night.
Is there any canonical evidence of the fate of Kira's two brothers? Other than the suggestion they are probably dead because they do not appear in the series. Have they ever been used in the novels?
Didn't Jadzia have a sister?? We never saw her either. Just cause we never see Kira's brothers doesn't mean they are dead. Of course, one could say that the fact that DS9 was located in Bajoran space means that it would have been "easier" for Kira's brothers to appear on the show than Dax's sister.
Jadzia's sister didn't grow up during a deadly occupation, and there were fewer stories where you'd expect her sister to show up. Her wedding was impromptu enough that you wouldn't expect her to be able to get there, so that leaves her trip to Trill, which she'd only be present for were she on Trill.
Most Bajorans who didn't escape and join Starfleet are on Bajor, and it's only a short travel distance between them. You'd think if they were alive they would have visited her time to time, unless as suggested they were on very bad terms.