The Power of Attorney is extinguished on death unless revoke by the principal. As to the Will, your mom may not have testamentary capacity (being of sound mind . . . ). The problems in the Will that have you concerned about appear to be of minor to no consequence. The major problem is "Harris but now changed to Mott" can be overcome with prior birth or baptismal records. Finally, problems in probating an estate normally occur if the Will is contested. If you get along with your siblings and there is agreement of division of assets then the court is not interested in such minor details.
