Baby names problems

So,as we don't want to find out sex of our first baby,we must have names ready for both genders.Now,myself and my husband liked the same names,so I thought it would be easy.It's easy for a boy -we already both picked Aleksander. But as for girl (even though we both love Abigail) it's harder. NOW for the reason why I'm not sure about it... before I was married,my crazy sister-in-law (she really is insane!) at some family event asked everyone what names will they give to THEIR children if they have some.So not thinking much about it,I share that I love name Abigail... to make long story short...she then gives that name to her newborn girl. (to my shock!) To make things worse,she only live for few days-due to genetic problems...Since then she just gone worse,making all different accusation to our family,and was so jelous of other babies born in the family.So only few months later she gives birth to another girl-again genetic problems...cause her to be born with Down Syndrome.She called Julie-Abigail.So once again,big troubles for the whole family,she's so bitter ever since...We tried to help her,they were welcomed in mom's house everyday,yet she was always looking for faults in everyone

My mom was under such a stress,we all as her kids decided that she doesn't deserve to be treated like that.So we basicly stop talking to them and have no contact whatsoever. NOW here is my question: would you still go ahead and use the name ABIGAIL ?Knowing that your insane sister-in-law can be upset /cause problems/drama etc.once she finds out??? What should I do?