There are indications that JWs may in the near future modify their guidance on blood products.
http://www.ajwrb.org/basics/abstain.shtml
The scripture was written long before the life saving procedure of transfusion was known about and the interpretation is very strict. I hope a relaxation or total abandoment of this directive does arrive soon.
In answer to the question, anyone has a right to deny any medical treatment that they do not agree with. To leave two children motherless is a tragedy. Unfortunately, for some people their faith is paramount to everything, even life.