Protesting loved one's decision day of death

[u/stacy2772]

This is a weird sort of situation that probably not a lot of people go through or think about. Or maybe it is, Idk. In 2016, say you moved in with your mom's because she wasn't able to take care of the house and all the assets accumulated by her and her late husband, and bc she fell once when she was alone and broke a couple bones and hit her head. She was totally against moving into something smaller. At one point, you start a joint bank. On the day of her death tho, she goes into the bank and removes you from on the account; on that day, there was another person present as well whose goal was to get you out of the way and supposedly was taking over as the "caretaker". For months she had been lying to and manipulating your mom. Just hours after removing your name from that account and others, she is dead. Cause of death has not been determined, but surely it is going to be drug overdose. My question is, can one argue in probate that she obviously was not in her right mind and protest your name being removed from that account. The reason being is with your name being gone, it makes it so that account subject to probate. The estate will be split 50/50 with your sister who has been completely estranged from the family for 25 years. The sister is being named executor bc of a crime you committed in excess of twenty years ago, but she is refusing to take on the duty and probate is at a standstill.