Who is Henry (Harry) Winthrop from The Winthrop Woman and what is their importance?

Harry is John Winthrop's son and Jack's brother. He farms tobacco in Barbados, and ultimately fails, leading to his return to London. He is described as immature and free wheeling, leading his wife Bess into a similar lifestyle. In the end, Harry drowns in a river in Salem. His pregnant wife is left to raise their daughter alone.