Every day after Shacharis, his father would learn for two hours, and was mapkid on this learning period his entire life. One day, a wealthy merchant knocked on the door of the Kotler family, and informed them that he would like to buy a sizable amount of furs. However, it was the set learning time of Rav Kotler. His wife knocked on the door of his room, once, twice, and three times, and urged her husband to utilize this opportunity for his business.
From Revach.net