These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Jamie's dad is gunned down in front of him when he's fourteen, and he is relentlessly picked on for the next two years. Then, he comes home to find that his mother has been kidnapped by Alexandru. He then learns that his dad sold out Blacklight to the same vampire that kidnapped his mom (not really).
His mom, Marie, is abducted by Alexandru and kept as a hostage for pretty much the whole first book. She is then turned into a vampire as her captor's last act of spite.
Larissa was turned into a vampire when she wanders into a dark alley at a fair and forced to abandon her family lest she eat them, she runs into Alexandru at an unspecified later time. The only reason he doesn't kill her on the spot was because he was Distracted by the Sexy, and she has to convince him that she was a vicious killer in order to survive. When he orders her to kill Jamie, she can't go through with it, and he horrifically mauls her as punishment. Also qualifies as Jerkass Woobie due to her behavior toward the beginning.
Kate happens to live on Lindisfarne Island when Alexandru attacks it and is forced to witness the sheer Gorn inflicted on her fellow townsfolk. At the end of The Rising, her boyfriend dies, too.
Paul Turner, in the later books. In the Rising,his son dies, resulting in a friendship with Kate, and it's revealed that he feels intensely guilty because he thinks he wasn't a good enough dad, up to losing sleep on the matter. And to add to it, in Zero Hour, he says that he has done possibly terrible things for the Department and he has to believe it was for good otherwise he might kill himself.