Ferris: (A Heartfelt and Humorous Middle-Grade Coming-of-Age Novel About Family, Ghosts, and Growing Up - For Kids Ages 8-12 in Grades 3-7)

I did a little googling- this is a great question! I came across this blog post which has a ton of suggestions. https://imaginationsoup.net/mystery-books-for-kids/ But also a Kate DiCamillo book I had not heard of! Ferris. It might be too old but here’s a link. https://a.co/d/02UeAtOB