They fucked up the timeline pretty big, Gillian and Nick are 18 when they are supposed to be 15. I'm not going to spoil things, but there's now way 15 year olds could do the things they are doing in this book.
That is an interesting problem to have. How do you represent someone pretending to be someone that doesn't exist with a non-existant family that doesn't want to not let her mourn the daughter that none of them know in anonymity?
The bowl of cereal has had me crying with laughter. That's the funniest thing I've read in a while. I can't believe that was in the book. Now I have to read that passage. Who in their right mind would break into a person's home to eat a bowl of cereal?
Gillian's autism was completely disregarded in Deception with no explanation. I used Doc Brown to show what I believe happened to her autism (and her sudden and impossible aging of 3 years to coincide with the book's timeline).