I remember reading the book in elementary school (mid 2000's) for some book report
The main character was a little boy who got a remote or some device from a wizard or something that let him reset time so he could relive a day over again.
I believe he had a dog (or some other kind of pet) and a younger sister. I remember a major plot point being him ignoring his sister and then she gets in some kind of serious accident (maybe with a bike) and ends up in a coma. I remember the coma very specifically because it was my first encounter with the concept and a big part of my book report was explaining what a coma was.
After that he resets the day and chooses to spend more time with his sister.
I swear the title was "The Power of Id" but I can't find any novels by that title either by google or by looking at my library's catalog.