LOL, yeah Judy Blume. I grew up in a small town/conservative society, and I remember being completely shocked and embarrassed by my first Judy Blume book around age 11 or 12. It was that book “Are you there God? It’s Me, Margaret.” The theme was young teen girls competing over who physically matured/got their period first. I remember wondering what planet those girls lived on.
So yeah, vetting books is a good idea and Judy Blume in particular does focus a lot on sexuality. If the child is old enough, some of her stuff will help make sense of some of the things that perhaps you and your spouse aren’t comfortable talking about with them yourselves!