A novel about a reclusive kid and his family with a morbid occupation. The author dedicated the book to his/her mother who loves to drink Persian tea. Please help me find this book.

(I know, this is not r/tipofmytongue, but I posted this exact same request two times to no avail)

The narrator of the book is not the reclusive kid in question, it’s someone who knew the kid and his/her family well.
If my memory is not messing with me, I think the morbid occupation of the family is disposing the corpses of people.
Thanks in advance!

by TheCozyShuttle