X, Y and Z, the sons of Mr A consult you on their father who has become irresponsible and wastes away all his money and assets. They are afraid that it will not be long before he has nothing left and will not have enough money to take care of himself. X, Y and Z also tells you that their father does not want to listen to their advice to stop squandering his money. Advise X, Y and Z what they can do to help their father and force him to stop wasting his money. Explain the legal principles involved and the process they must follow to do so accordingly. In your answer refer to case law.