The improper use of a position of ascendancy over another to procure a contract or gift inter vivos. In certain relationships, such as those of parent and child, guardian and ward, solicitor and client, and doctor and patient, the power to influence is presumed. In other cases a relationship of influence may be proved. Where there is a relationship of influence and undue influence is not disproved by the influential party, the transaction will be set aside as invalid. Furthermore, where there is no relationship of influence, it is still open to the plaintiff to allege (and prove) that the defendant actually influencenced him/or her. In probate proceedings there are no presumptive relationships, and undue influence must always be proved by the party who alleges it.