Hey Kiddo by Jarrett J. Krosoczka (click on title to preview the book)
“In kindergarten, Jarrett Krosoczka’s teacher asks him to draw his family, with a mommy and a daddy. But Jarrett’s family is much more complicated than that. His mom is an addict, in and out of rehab, and in and out of Jarrett’s life. His father is a mystery — Jarrett doesn’t know where to find him, or even what his name is. Jarrett lives with his grandparents — two very loud, very loving, very opinionated people who had thought they were through with raising children until Jarrett came along.”