When my sister had surgery on her head she could not balance. I bought her a Sun tricycle. She rode it for a summer at the beach.

I was thinking about taking it back now that she can ride a two wheeler again. It has a 3 speed internal gear and is awful on the hills where I live. I think a smaller front chainring would help. It is downright dangerous going downhill if you turn without slowing down more than you would think you need to.