If you can prove undue influence or incompetence-the will be be set aside.
You need a probate litigation attorney ASAP.
The answer given does not imply that an attorney-client relationship has been established and your best course of action is to have legal representation in this matter.
Have the SC lawyer file objections with the court ASAP. You should be able to get the will knocked out for lack of testamentary capacity.
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I agree with the other two responses. It appears you are in for a fight. It also sounds like you are already represented by counsel, so these are issues that you need to address with your lawyer. Your case is complex and you have issues not only with the Wills in question, but also whether or not it was appropriate (or permissible) for your sister to change the nature of your mother's bank accounts. It may be that you can have those changes set aside by the court.
Best of luck to you!
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