I'm sorry, this is not really my cup of tea.
The book doesn't have a great flowing story. Things happen with no context. All of a sudden Draco's son is best friend with Albus, Harry's son. It's just, doesn't feel like a Harry Potter book. The books give charm, they have a flowing story and very vivid details, and this just doesn't feel like it. I refuse to believe this is canon. The villian doesn't make sense. Voldemort had a daughter? When did this happen? When did he have a daughter? These are questions unanswered. We thought the series ended. Maybe it was best JUST to leave it be.