Vanessa's adoptive parents were an implausible mess. Why would they have resorted to an illegal adoption, if 10 years later it was still possible for her mother to get pregnant? They should have been able to swing a legal adoption, if she was 35 or younger. Very confusing. The story with Miranda's parents was more coherent, however, both back stories seem designed to provide the women with psychological issues that were clearly a result of "nurture" rather than "nature".
I did laugh a bunch at the description of breaking into Palm Grove Villas at the Four Seasons Nevis. Then I spent way too much time looking at pictures of Caribbean resorts with similar kinds of housing, and then contemplating a romantic suspense novel with a chase scene on the monorail at Disney World. *snicker* Books do weird things to my head.
In the larger arc, more deaths are attributed to the Big Bad Guy in the Background, and a lot is made of the tattoos on the back of the babies necks. With "66" and "hi" or "14" as the first two found (and the other triplet dead a couple months ago), I'm betting something like "Higgins" for our Big Bad guy.