YA Fantasy about boy who is walking home and finds an item (99% it’s a book) in the snow. His kid brother’s name was Sterling. Read late 2000s/early 2010s. Spoilers ahead.

[Grace]

Read as a kid in maybe the late 2000’s or early 2010’s. I remember the author was a girl who started writing the book when she was in high school.
It was a third world story, set in a city where there was a strict curfew and the rules were quite rigid and maybe military-esque. There were two MCs, the first one was a boy who was walking home (after curfew?) and found a book (I’m so sure it was a book) in the snow. It later turned out to be a magical (?) book in some way, or at least very important to the plot.
He had a little kid brother called Sterling, who got sick and died maybe half way through the book. It was super depressing. They lived with their grandmother, I think.
There was another MC, a girl. I don’t remember much about her.
Later in the book there was some kind of time/dimension travel or something? I’m pretty sure. I just clearly remember the MC hiding from soldiers then being found by one, a young soldier who he shot with a handgun. I remember the force of the gun knocked the MC off his feet. And he felt really guilty about it.
The cover was dark tone, maybe bluish. I don’t remember anything about the title but this is driving me CRAZY.

[Bridget]

The Eyes of a King by Catherine Banner

[Kris]

Bridget's suggestion of The Eyes of a King by Catherine Banner sounds like your book.

Google Books preview:

https://books.google.com/books?id=CpD...

Quotes from the book:

- [page 1] I began with the book, and the snow.
The snow began to fall as I walked home.
- ... because Stirling was sick. (...) "Leo, stay with your brother for a minute...
- "Finding a magic book. As long as it is not evil magic."