Hmm I can't say what is normal, because I'm not sure there is a normal. I've had bloody and violent dreams all my life. Most of my dreams as a kid were nightmares involving myself or someone I loved dying. Sometimes violently.
I don't think it's that unusual for kids to have dreams about death. Kids are always trying to work over things they don't quite understand yet and this may manifest in dreams. I think the unhappy childhood could have exasperated these dreams.