In the case Bob is old and totally dependent on his niece Julie and when Bob signs the contract to sell a parcel of his land to Julie at 75% of the market price, he is definitely doing it against his will and under undue influence. Undue influence in English law is a field of contract law and property law whereby a transaction may be set aside if it was obtained by the influence by one person (Julie) on another (Bob), such that the transaction cannot "fairly be treated the expression of (Bob's) free will"