I would be interested in reading something else this author has written to see if her writing style has matured at all. There are good intentions and some relatively good character building, but a lot of this just screams of an amateur effort.
1) Errors, errors everywhere. I should have known that the professional editor in me was going to have a hard time when the book was dedicated to, among others, her daughter... who was also her proofreader. It shows. There wasn't a single page that didn't have at least one grammar/punctuation/sentence structure problem. Main offender -- the dreaded comma splice. One one page, there were 4 in a row. And on another page, there were two sentences that each had two comma splices in them. If it was just one or two I wouldn't comment, but when there are over 100 grammatical errors because the author didn't shell out a couple hundred bucks for a professional copyeditor, I cringe. If you want to be serious about your work, you need to make the investment -- and that means if you know you aren't good enough at writing technically well, then you need to find someone who is before you put yourself and your work out there.
2) Foreshadowing with the subtlety of a hammer. This is a pet peeve of mine with self-published authors. It seems that a lot of authors don't think that the reader is smart enough to think about what's happening on their own, so they need their characters to muse internally and ask questions that the reader should be asking if they are paying attention. But inevitably, the character just draws our attention to something so strongly that it ruins any surprise later. Like when the character goes "Wait, why was THIS happening now? It seemed sooooo strange, what's going on? Oh well I'm sure it's nothing......." And then we are supposed to be surprised with the character later on when we both "discover" that it actually WASN'T just nothing... lol o rly? No kidding? In general, internal musing is a bad sign when it takes up more than 25% of the story, because it seems to just be filler, rehashing what has already happened in case we didn't "get it" the first time around. I also think authors tend to do this when they want to have a surprise ending and want to make sure we know how clever they were, so we have to be reminded all along that there is a puzzle.
3) Really odd emotional reactions to things. In the first chapter, everyone is just finding out that her sister's husband is missing and a cute detective comes to talk to them... and the chapter ends with "The question was... who was his [the detective's] type?" Really? THAT'S the question? Second, when our main character and her sister find out that the niece is also missing (which I put in here because it's in the main book description, so I figure this isn't a spoiler), they......... have a girl's night and giggle and watch movies. Seriously. And then a police offer finds out something bad happened and he's giddy about it. It's just... really odd and feels like the characters aren't reacting like humans, but are railroaded into the outline the author had for the book. She wants to set up a romance so she makes our no-nonsense main character muse about him just after she hears bad news even though that makes no sense.
The writing itself isn't particularly spectacular. As I've mentioned before, there are a large number of comma splices and other errors. This is a problem in and of itself, but it also means that she's writing the same kind of sentences over and over and over again. "[complete sentence],[complete sentence]". It lacks a poetry or cadence. Even with a good editor, the focus for this author seems to be plot over style. There's nothing necessarily wrong with this, but combined with the grammatical errors and the other issues, this work feels amateurish.
I was looking at her page to see what other books she has written, and I see there are quite a number of them. Almost 10? And they have all been published in the past 2 years. 10 books in two years, with severe grammatical errors? It really feels like she's just cranking them out and going for quantity over quality. I would really urge her to slow down, hone her craft, focus on the words as well as the story, and... please, get a good editor! A good editor will help clean your story up and allow you to present yourself in the most professional way possible.