A decedent may be of sound mind but yet may be a victim of undue influence. Decedent Dorothy became persuaded that her friend Alta was a psychic who could communicate with Dorothy's deceased relatives. Not surprisingly, these 'relatives' through Alta's clarevoyence instructed Dorothy to turn over money, stocks and a condominium to Alta. After death the transfers to Alta were invalidated: "...Alta's control over Dorothy's mind and her influence so pervaded Dorothy's thought processes that they completely subverted her will to the wishes and domination of Alta, and this imposition continued from the moment Dorothy was convinced Alta was a true psychic and medium to immediately before her death." The evidence of undue influence was clear, even though it was circumstantial.
Estate of Baker, 131 Cal. App. 3d 471, 482 (1982)