Hello,
Welcome to Health Care Magic.
Thanks for writing.
I am Dr.Saddiq-ul-Abidin. I have read your question completely, i understand your concern and will try to help you in best way possible.
The history you gave me about your sister and the way symptoms developed and progressed, I am of the opinion that this was natural numbing of leg when blood supply of food is stopped for some time.
You would also have observed if someone sits for long time on his legs, like few people sit on restroom seat for longer periods of time their blood supply to legs gets collapsed and then the leg gets numb.
As the person stands up or the blood supply is re-established, the leg with time gets to normal, and during that process sudden pins and needle sensation is felt which some people describe as aunt bites,this is natural and shouldn't be worried about.
I would suggest you to ask your sister if she was sitting for some times on her leg before this happened the it's ok, it was this natural response that i described above. If This was out of no where then she can wait till she feel next episode , if this keeps happening again and again this can be
nerve impingement and she should consult a doctor for that. Otherwise she doesn't have to worry at all.
I hope this answered your question.If you have more queries I am happy to answer.Otherwise rate and close the discussion
Regrads.
Dr.Saddiq ul Abidin
M.B.B.S(Licensed Family Physician)
Resident Medicine.