- Cooper's father died during open heart surgery in 1978, and about 10 years later, his older brother, Carter Vanderbilt Cooper, committed suicide by jumping from the 14th-floor of his mother's New York City penthouse apartment.
- Vanderbilt, its 125,000 acres constituting what is probably the finest country place in the United States.
- The University block (an office building owned by Syracuse University), the Union Building, the Onondaga county savings bank and the Syracuse savings bank are among the most notable business structures; and the Onondaga, the Vanderbilt House and the Yates and St Cloud hotels are the principal hotels.
- Vanderbilt in 1866 became attorney for the New York & Harlem railway, in 1869 was appointed attorney of the newly consolidated New York Central & Hudson river railway, of which he soon became a director, and in 1875 was made general counsel for the entire Vanderbilt system of railways.
- He became second vice-president of the New York Central & Hudson river in 1869 and was its president in 1885-1898, and in 1898 was made chairman of the board of directors of the Vanderbilt system.