ERROR IN THE MIDDLE NAME

The middle name of my father is RIVERA. He used that middle name in all his important documents. His siblings also use the middle name RIVERA, too. Even on his Certificate of Live Birth, the middle name indicated is RIVERA and the maiden surname of her mother indicated was RIVERA. Also in the Birth Certificates of his children, RIVERA is his middle name indicated. However, on the personal documents of his mother (Birth, Baptismal, Marriage and Death Certificates), the surname indicated was consistently REVERA, instead of RIVERA. My concern is, instead that my father files for correction of clerical error, can he just file an affidavit stating that he shall just bear the name RIVERA for the rest of his life, instead of REVERA (the correct one), since it has been his practice to use RIVERA. Hope someone can help. Thanks.