Children of Memory is the third (and final?) book in the Children of Time saga. I have very mixed feelings about this book (and also this series). If I had to sum up my feelings, the last 50 pages of this book are absolutely excellent but the middle ~200 pages drag on for quite some time. If I had to review the series as a whole, I am glad I read these three books personally, but my recommendation for others who hadn't read any would be to read the first book and stop there.
One thing I think this series does well is that each book has a very different vibe overall. Book one is very space opera / evolutionary theater, book two adds in a significant horror element, and book three feels more like a mystery (fairytale)? of strange contradictory events. I strongly agree with Tak, who described this third book as Locked Tomb-esque.
The technological development arc in this series reminders me a little of Cixin Liu's Remembrance of Earth's Past series. By book three of each of these series, the technology level has just gone so far into post-human / galaxy teleporting / immortality / body uploads / consciousness-splitting developments that it almost feels disconnecting to me as a reader. What are the desires and needs of people who live like this even like? I think this book gets into some of what that might be, but in both of these series I found it harder to connect with characters as time went on.
Similar to the previous two books in this series, which each have their own featured uplifted animal, this book also brings in some extremely smart corvids. Other characters are not sure what to make of them and spend a lot of time trying to figure out if they are sentient or not. (The birds say they are absolutely not.) I found the birds Gothi and Gethli to be very endearing characters. I love love loved the small interstitial chapters where they are wittily talking to each other and making jokes. I felt like it nailed "birds are really interested in shiny new things and uninterested in everything else" angle as well as the "corvids are both extremely chatty and smart" one.
This book also adds a lot of good development for characters from book one and book two. I like that we get to see extra sides of Kern(s), as well as a significant perspective from a character who is Those-of-We trying to be a Human named Miranda that they knew specifically. They're coping with the tension of wanting to know everything, with being a terrible entity in the past that they're ashamed of, with various emotional traumas, and with the stress of pretending to be one thing when really they are many many things at once. I felt like the book two perspective on Those-of-We was necessarily limited and I was glad that book three has a chance to let them shine.
I feel like any discussion of the end of the book is going to be extremely full of major spoilers, so I will leave that in a follow-up comment. Suffice it to say that I felt like the ending to this book was as solid (if not more solid) than book one and really tied together everything that the book put out there in a satisfying way.