Growing up in Rockville Center, NY, Brennan quickly grew to be an idol for his younger siblings. At a height of six feet, seven inches, he was a natural basketball player in high school and was nicknamed "Zelmo" after Zelmo Beatty, a popular basketball player at the time.
Brennan's career was jump-started fortuitously as a bouncer at local night clubs on Long Island. Before long, his natural talent allowed him to rise to the position of manager, and before leaving the business he was owner of several clubs, including Solomon Grundy's in Bay Shore.
For the last ten years of his life, Brennan worked as a senior vice president and limited partner at Cantor Fitzgerald as a government securities broker. He became an ardent supporter of the New York Police and Fire Widows' and Children's Benefit Fund headed by Rusty Staub, former New York Mets player and longtime friend.
On September 10, 2001, Staub and Brennan met for the last time to discuss plans for a November benefit for the wives and children of dead firefighters and police officers.
Brennan worked on the one-hundred and fifth floor of the World Trade Center. On September 11, 2001, he was amongst the thousands killed in a series of terrorist attacks carried out against targets in the United States. He was survived by his wife, mother, five siblings, and ten nieces and nephews.
Frank Brennan, a good-natured, caring, and generous man, came from a large family with few opportunities and succeeded in climbing the ladder of success. Regrettably, his name has been tragically reduced to merely another on a very long list of empty spaces in American history, holes torn through the lives of innocent families. In remembering his story along with those of the thousands of others who died that day, it may be possible to offer them some hope of justice and remembrance.