This article tells us about Jack's older brother, Bill. I can't help but notice that Jack's and Bill's lives paralleled one another very closely through World War II. After that, they each went their own way. Jack pursued acting as a means of making his name known in order to sell his paintings, while Bill continued to pursue art as his profession, both on canvass and as an art director and instructor.
Many thanks go to Sheila Sova of the United States Merchant Marine Veterans of World War II.