I hope the prosecution have a ace up their sleeve about the lack of blood evidence.
My childhood bathroom had a slanted ceiling and the amount of times we would forget and bang our heads and even a slight knock on the sharp edges would cause bleeding. Which is why I have always they would bleed heavily.
When I was around 6-7 years old, my parents bought me a wooden, purple baseball bat. My neighbor friend was around 8-9 years old. He accidentally swung it, with all of his strength when I was standing behind him and the bat broke into 2 pieces from hitting my forehead. I had a huge "egg" size bump on my forehead as a result. However, there was NO cut/laceration or bleeding from the blow. So, I can understand her when she says that about having a cut/laceration vs a blow without one.
I also know a small cut/laceration anywhere on our skulls can bleed profusely as well. Even though the bat was wooden, it literally shattered into two pieces, right down the "fat" part of the bat, down to the handle. If that makes sense?