Thomas Francis Leahy, the oldest of the two children of Richard T. Leahy and Honora ("Nora") O'Connor, was born in Chicago, Illinois, on January 6, l 926. He attended St. Matthew Grammar School and entered St. Rita High School (1941-42). both in Chicago. His high school education was interrupted by World War II, during which time he served in the U.S. Navy (1 943 -45), receiving an honorable discharge on December 18, 1945. Upon his return to Chicago he earned diplomas in electricity and radio-electronics at Coyne Electrical School and, taking advantage of the Veteran' s Training Program, obtained his high school diploma from Crane Technical High School in January 1950.

On November 2, 1950, he entered the novitiate for cooperator brothers at St. Thomas Aquinas Priory, River Forest, Illinois, was given the religious name, Paul, and made his first profession of vows on November 3, 1951. He was assigned to maintenance at St. Thomas Aquinas Priory, a ministry which he continued there for twenty-seven years. Brother Paul professed his solemn vows on November 3, 1957. His interest in electronics served as a hobby as well as ministry and he earned additional certificates in this field from the De Vry Institute of Technology, Chicago, Illinois.

In 1978 Brother Paul was transferred to St. Thomas More Center, Tucson, Arizona, where he joined the staff of the student center. A year later he returned to Chicago and joined the maintenance staff of St. Pius V Priory, a ministry which he continued until 1995 when he was placed on limited service. He continued to reside at the Priory until November of 1 999 when his health needs required his transfer to Resurrection Life Center in Chicago,

where he resided until his death. During the last year of his life his health continued to decline and on February 17, 2003, he died at Resurrection Hospital, Chicago, Illinois. His funeral Mass was celebrated at St. Pius V Church, Chicago, on February 21st and he was buried in the Dominican Plot, All Saints Cemetery, Des Plaines, Illinois.