The trial court did not abuse its discretion by finding an elderly victim to be competent. The witness correctly testified to his full name and birth date and where he lived. He was able to correctly identify family members, the defendant, and his own signature. He understood that he was at the courthouse, that a trial was occurring, and his duty to tell the truth. His testimony also demonstrated his ability to tell the truth from a lie. Noting that some of his answers were ambiguous and vague and that he was unable to answer some questions, the court concluded that it would not be unusual for an elderly person to have some difficulty in responding coherently to all of the voir dire questions.