Sarah Cooper Hewitt and her sister, Eleanor Cooper Hewitt were abord the Lusitania in 1907. Sarah Cooper Hewitt (a very well-known and wealthy family of socialites) was I believe the mother of Edward L. Hewitt, father of the Adams car but more well known for his books about fish and fishing. But the Lhe Lusitania wasn't sunk before 1915, so I think the connection is very weak.
The is another: after the Titanic survivors landed in America, they were nursed by many "women of prominence" as said the New York Times in the following excerpt. One of them was Mrs Edward Hewitt, which we can guess is logically our Edward L. Hewitt's spouse.
"...Women of prominence could be seen moving about from task to task. Miss Anne Morgan was always busy, Mrs. August Belmont and Mrs. Eugene Kelly were helping with this case and that, Mrs. Edward Hewitt was a tower of strength, and Mrs. Henry Dimock was tireless as her bundles of clothing arrived, stack on stack, and her motor car carried her from one errand to another..."