Not much to say about this one. The killer wasn't a surprise - I'd already expected them to be the killer. I do have reasons for that, but sharing them would make who pretty obvious.
It was kind of funny that Ramirez ended up taking care of the babies for most of this book and it's Maddie who's figuring out who the killer is. That second part isn't that new, but Ramirez asks her to help him! Normally he's telling her to leave it alone and let him do his job, but he can't do his job in this one since he's been suspended - for fighting but the guy called Maddie a bitch and grabbed her. I can't blame Ramirez for punching him, but you'd think a cop would have more emotional control then that.