Your sister should consult her primary care physician. She should then consult a neurologist. They both will attempt to rule out medical causes. Before considering a psychological problem, it’s common practice to eliminate physical causes.
Fortunately, her episodes don’t happen often, they don’t last long and she has never been injured. Though they seem relatively innocuous, they should not be ignored. They are unusual and not normal. The cause should be identified.
If she hasn’t done so already, she should document her experiences. Hopefully, she can do that with the assistance of a physician who will help her in identifying the problem. I wish you and your sister the best of luck. Please take care.
Dr. Kristina Randle