From the Book "Peter Robinson's Settlers" by Carol Bennett, on page
103, it states:
At least 3 of Micheals's (Leahy) children married other Robinsons settlers who had come from their home parish, Brigown. John Leahy married Joanna Tobin who had also come on the Fortitude. Descendants include Father Harold Leahy, Sister Rosemary Leahy, and the late Sister Helene Garvin, Superior general of the Sisters of St. Joseph at Rochester, NY.
John may have married Johanna' Tobin's sister, Mary. Just speculating, but there was the following in the St Joseph records:
Married May 11th 1850 John Leahy widower and Mary Tobin both of Douro Bishop Philan having dispensed with the publication of banna. Witns. John Condon, Catherine Ceacey (?) and Mary Fahey. H. Fitzpatrick, Priest.
1851 census
John Leahy, Farmer, Ireland, Catholic, 58, married.
Johana Tobin, Ireland, Catholic, 40, married.
John Leahy, Canada, Catholic, 19, single.
Michel Leahy, Canada, Catholic, 17, single
Mary Leahy, Canada, Catholic, 15.
William Leahy, Canada, Catholic, 13.
Martin Leahy, Canada, Catholic, 11.
Shanty, 1 story, 1 family.
4 attending school.