He was born and raised in New York and moved to San Antonio in 1978.
He was a member of the 11th Airborne Division while serving in the U.S. Army.
John was a dedicated employee of PaineWebber for over 20 years until his retirement. In recent years he was an independent broker.
Some of his many loves were coaching Little League baseball in New York and golfing.
He was preceded in death by his sister, Marion Kern, and by his parents.
He is survived by his wife of 26 years, Mary; sons, John E. O'Neill IV of Long Island, Phillip O'Neill of Pennsylvania, Robert McClay and wife Tammy of Dallas; daughter, Kim McClay of Colorado; brother, Brian O'Neill and wife Cookie of Idaho; granddaughter, Megan; grandsons, Robert, Matthew, Luke, John, and Joseph; numerous nieces and nephews, and a host of loving friends.