I was looking over the last few books I read and I realized that they all have something in common: physically or mentally absent parents.
Homesick, by Kate Klise
The mother leaves town and the father is a depressed hoarder.
Don't You Dare Read This Mrs. Dunphrey, by Margaret Peterson Haddix
The father is abusive and leaves and the mother is depressed and negligent.
The Ghost of Graylock, by Dan Poblocki
The father leaves to pursue acting and the mother gets depressed and needs time to herself so she sends the kids to stay with her sisters.
Variant, by Robison Wells
The children at the school all have no families.
The funny thing is, I didn't even notice until I went to write reviews.