Quick supernatural read about a brother and sister pair who are partially turned into vampires and have to kill the head vampire to go back to being human. The influence of The Lost Boys is clear - the book is perhaps a little too reminiscent - but it's been years since I've seen the film so I can't really give a play by play of any similarities. 

The relationship between the siblings was the most convincing thing about the book, I think; certainly more convincing than the vampires themselves. There seems no real reason for Derek to try to form a family with these two and their mother (why does it have to be them?) and the underlying romantic relationship between Callie and Maeve was distracting, and not in a good way. When you've only got three days or so to safeguard your humanity, perhaps it's time to prioritise your actual life over your social life, yeah? It's hard for me to feel for Callie when she comes across so scatterbrained.