As pastor, Father Brophy divided his labors among St. Mary’s Wappingers, the ore beds at Sylvan Lake in Beekman, and Fishkill Landing. Anyone who wished to hear Mass more than once a month had to travel to where the priest was that week. People wishing to receive Communion had to fast from midnight and folks coming in from Sylvan Lake often brought a loaf of bread in their pockets to sustain them on the long way home. Denis Sheehan succeeded Father Brophy as pastor of Wappingers Falls, Fishkill Village, Sylvan Lake and the Beekman area in 1853. He was also responsible for ministering to the mission parishes in Fishkill Landing and Matteawan until the foundation in 1857 of what eventually became St. Joachim's in Beacon. It is reported that in winter, priests from Wappinger used to walk across the frozen Hudson River to say Mass in Marlboro and Milton. Denis Sheehan was a great temperance man and organized St. Mary's Total Abstinence and Benefit Society which had a membership of 175 by the time of his death. This was a period of great growth in Wappinger and saw the founding of the first newspaper, the library, Drake School (the present VFW Hall), the Garner and Johnson Fire Companies, the establishment of Sweet Orr and Company, eighteen saloons, and the incorporation of the village. Father Sheehan died on October 27, 1875 and was buried in St. Mary's cemetery. On the day of his funeral, all the factories in Wappinger closed down and everyone turned out to honor him, including officials of the Garner Print Works. In July 1876, Father Charles M. O'Keeffe took charge of the parish and began construction of a new church to replace the original structure, which despite repeated additions, had become too small for the growing congregation. The excavation of the cellar was done by men of the parish under the leadership of Mr. James Campbell, a stonemason. Much of the stone was taken from a small quarry on Fulton Street. In appreciation, Father O'Keeffe placed their names in the cornerstone of the church with other records. The cornerstone was laid Saturday, September 27, 1877 by Cardinal John McCloskey. A popular and gifted administrator, O'Keeffe was elected a director of the Wappingers Savings Bank on January 26, 1877, second Vice President in January 1878, and first vice president in January 1880, a position he held until being transferred in 1885 to St. Charles Borromeo in New York City.