Half-Blood Secrets by Natasha Brown

Deane has been a Genus Society enforcer for nearly a century and isn’t used to putting others’ needs first—that is, until he becomes the foster parent to Riley, an orphaned teenage blood-sucker. Not only are the boy’s dietary needs in question, but Deane must travel to Miami to investigate the boy’s dead father to learn more about this dangerous new breed.
Verity has lived a quiet existence on the Florida coast for years, but a mysterious message from her estranged brother leaves her with more questions than answers. When an exotic tiger is brought in to her veterinary clinic, it proves to be more than a little coincidental.
As Deane observes her from his cage, he wonders if the beautiful woman is as kind-hearted as she seems or if she is as volatile as her dead brother while Verity is faced with a life-altering decision—being loyal to her vampire kin or siding with the changelings who killed her family.