i am impressed that you have gotten this far without an attorney. While you may not need the affidavit for mediation, you would need them for the evidence to be admissible at trial.
Kendall Cockrell is an attorney with The Cockrell Law Firm in Beaumont, Texas. None of the opinions he states on this site constitute an attorney-client relationship. For more information, contact The Cockrell Law Firm. Contact information available on Kendall Cockrell's profile on this site.
Adding to Mr. Cockrell's answer, if you are going to court, you probably aren't mediating. That sounds like trial. If you don't have an attorney for the trial of a will contest, you are in trouble.
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What you need is a lawyer.
In order for the documents to be admissible, there should be a Business Records Affidavit. You need to file and serve that according to the rules.
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