His popular father had been the most prosperous merchant at Strabane, controlling a large proportion of the general business of two or three Northern Irish counties. As a ship-owner, for many years he sent emigrants across to New Brunswick and the United States. But, by the 1840s, Leslie Gault's finances were hit by severe losses in the Grain trade and by the removal of duty on Baltic timber. On top of these difficulties, three of his ships were lost at sea while the cargoes of his five remaining ships were being thrown on a depressed market, draining him of a lifetime's savings. In 1842, his father decided to make a new start and sailed with his family to Montreal, Quebec. On arriving, his mother fell ill and was advised to return to Ireland, and only nine months later his father died of cholera.