cASE#2 Has to be canadian law

Prior to his death, Percy Cameron owned substantial property but did not make a will because all his property was held jointly with his wife and would pass to her as survivor.He did, however, express to his wife that she should make some provision for his brother and his children.

Shortly after Percy's death, his wife, Grace, went to a lawyer and told him that she had promised her late husband that she would give certain things to his brother and that in case anything happened she wanted to get it in writing.Accordingly, she signed a written document prepared for her by the lawyer, promising that as soon as the business affairs of her late husband were settled she would give $100,000 to the brother.The document contained a seal adjacent to her signature and was given to the brother.

A misunderstanding subsequently developed between the wife and the brother, and Grace refused to pay him the money.The brother sued for the money.What is the main legal issue? Explain whether the brother would succeed in his action.