Legal Principle: The act of using influence on another and taking undue advantage of that person is called undue influence. Factual Situation: An arrangement was made between the fathers of a groom and a bride before their marriage that each would pay a certain sum of money to the husband. Father of the boy paid the promised amount but his wife’s father failed to pay the amount. The boy sued his father-in-law for the recovery of the promised amount of money. Issue: Whether the boy can recover the money. Decision: