Not holding out much hope but here goes.
I read it was a child in the mid 90s when I was probably 10 or 11.
It's a fiction chapter book, the story was about a teenage girl and I just remember that her dad was an ex writer and they were living off the Royalties of his book.
I think maybe the dad was unemployed now as I seem to remember them having not much money.
I know it's a long shot!