His wife, Caroline Schermerhorn Astor, served as the leader of New York society's "Four Hundred" during the Gilded Age.

[citation needed] Unlike his business-oriented father, William Jr. did not aggressively pursue an expansion of his inherited fortune.

Instead, he preferred life aboard the Ambassadress, at that time the biggest private yacht in the world, or horseback riding at Ferncliff, the large estate he had built on the Hudson River.

[8] William Jr. often spent winters aboard his yacht in Jacksonville, Florida, and he was responsible for the construction of a number of prominent buildings in the city.

Astor enjoyed his development and purchased a railroad that connected the town to the "Great Lakes Region" of Florida.

He donated the town's first church and the land for the local non-denominational cemetery, and he also helped build a schoolhouse, both of which are still standing today.

[9] The town boomed, and Astor, with an eye on the large New York market, expanded his interests to a grapefruit grove; this fruit at the time was only available on a very limited basis in other parts of the United States.

"[14] William Jr. had little interest in society parties, and reportedly, Lina would try to keep him at his club late to prevent him coming home and sending the orchestra out and his children to bed.