Francis Patrick (F. P.) Hennessey was born on the 30 July 1884 to Alice Curley (1850-1932) and William Hennessey (1843-1930) of Fort Augustus and Charlottetown, Prince Edward Island. Francis had two brothers who survived infancy, William James and Paul "Ambrose". William was a carpenter/contractor who built his own house at 51 Euston Street, as well as the house at 66 Rochford Street for his brother Francis in 1916. Both Ambrose and Francis were of an athletic nature and participated in the Pastime Club, a sport and recreational club at the turn of the century. Although he enlisted, Ambrose did not see active duty in World War I, contracting the flu virus at the training camp in New Brunswick and dying in New Brunswick in 1918. Ambrose may have been F. P.'s partner in The 2 Macs drugstore.

Following an apprenticeship as a drug clerk at the firm of George A. B. McDonald and Daniel A. McKinnon in Charlottetown, Francis P. Hennessey formally studied pharmacy at the Ohio Institute of Pharmacy in Columbus, Ohio, receiving his diploma in 1911. He continued to work for the MacDonald & McKinnon drugstore (commonly known as "The 2 Macs"), until he purchased the store ca. 1915. The 2 Macs drugstore was originally located at 154 Kent Street, and by 1909 it had moved to 149 Great George Street. The drugstore operated until at least 1937. As well as operating the drugstore, F. P. also served for a time as city councillor. The Hennessey family enjoyed boating. F. P. Hennessey had two small motorized boats, the "Princess Pat" and the "Dixie Girl". The "Dixie Girl" won a racing cup between 1916 and 1922. Before his death in 1924, F. P. bought land for a cottage on the Watts Road in Grand Tracadie. The family did own to the high water mark, but a portion of the land was expropriated by the National Park in the 1930s. The family cottage was completed in 1935 and is still owned by the family in 2009. At the time of his death, Hennessey was president of the Abegweit Athletic Club, Secretary-Treasurer of the Provincial Pharmaceutical Association, a volunteer fireman, and a member of the Civic Housing Commission. He died suddenly of a stroke at home on 23 June 1924.

Stella Marie Mullen (13 May 1887-19 January 1978) was born to James L. Mullen (1861-1941) and Mary Hynes (1860-1933) of Covehead, and later of Charlottetown. Stella's brother, Louis W. Mullen (1896-1953), saw active duty in World War I, and her sister, Viola E. Mullen (1899-1987), was active in sports. Viola became a nun, but she left the convent to become a teacher of invalid children in Boston. Other sisters listed in the 1911 census were Ethel B.(1888-1973), who became a successful businesswoman with her fashion company, The Sportswoman, Inc., in New York and Palm Beach; Leah M. (b. 1890), who with her husband, Henry Gregory Jenkins, owned the similarly successful fashion house of Jenkins of Paris, based in Paris France; and Annie (1892-1968) who married Ray MacDonald of Charlottetown. Their youngest sister, Blanche J. (1894-1900) died of measles.

Francis (Frank) P. Hennessey married Stella Marie Mullen on 27 November 1916. Frank had courted Stella for many years until he was established in his profession, business and property holdings. As soon as their home was completed, they married, and all their children were born and grew up in it.Their eldest son's birth occurred a few days after the Halifax Explosion in 1917, and since most of Charlottetown's medical professionals were gone to Halifax, F. P. had to trudge through a snowstorm to collect a nurse to assist with the birth. Family legend says that he carried the nurse to his home on his back in the storm. F. P. and Stella had four children: Francis "Frank" Louis (1917-1987; m. Dorothy Saunders); Ambrose "Amby" Everett (1919-1946); Stella "Bonnie" Ethel Blanche (1922-2004; m. Ernest Joseph Howatt); and Louis (Lou) W. (1924-2008; m. Mary Mitchell).

Stella Marie Mullen (13 May 1887-19 January 1978) was born to James L. Mullen (1861-1941) and Mary Hynes (1860-1933) of Covehead, and later of Charlottetown. Stella's brother, Louis W. Mullen (1896-1953), saw active duty in World War I, and her sister, Viola E. Mullen (1899-1987), was active in sports. Viola became a nun, but she left the convent to become a teacher of invalid children in Boston. Other sisters listed in the 1911 census were Ethel B.(1888-1973), who became a successful businesswoman with her fashion company, The Sportswoman, Inc., in New York and Palm Beach; Leah M. (b. 1890), who with her husband, Henry Gregory Jenkins, owned the similarly successful fashion house of Jenkins of Paris, based in Paris France; and Annie (1892-1968) who married Ray MacDonald of Charlottetown. Their youngest sister, Blanche J. (1894-1900) died of measles.

Stella Marie Mullen married Francis (Frank) P. Hennessey on 27 November 1916. Frank had courted Stella for many years until he was established in his profession, business and property holdings. As soon as their home was completed, they married, and all their children were born and grew up in it.Their eldest son's birth occurred a few days after the Halifax Explosion in 1917, and since most of Charlottetown's medical professionals were gone to Halifax, F. P. had to trudge through a snowstorm to collect a nurse to assist with the birth. Family legend says that he carried the nurse to his home on his back in the storm. F. P. and Stella had four children: Francis "Frank" Louis (1917-1987; m. Dorothy Saunders); Ambrose "Amby" Everett (1919-1946); Stella "Bonnie" Ethel Blanche (1922-2004; m. Ernest Joseph Howatt); and Louis (Lou) W. (1924-2008; m. Mary Mitchell).