According to The Story of the Family, Winifred Conlin Sr. had a daughter named Winifred and a granddaughter named "Winifred Gillen". Her grandson was Father Gillen. This suggests that Winifred Conlin, the daughter, was married to a Gillen. We really have no idea when this Winifred was born, but it was before 1900.
No more records for Winifred Conlin or Gillen have been found in Ontario, Canada through FamilySearch, FindAGrave, or the censuses. If, as I suspect, this family moved to the U.S., then they will be much harder to find without knowing which state or city they lived in -- and Margaret Prendergast did not mention that. So far, searching for a Winifred Gillen with mother Winifred Conlin has produced nothing helpful.
Ancestry.com may help with church records. These Conlins were Roman Catholic.
Featured Asian and Pacific Islander connections: Winifred is 30 degrees from 今上 天皇, 23 degrees from Adrienne Clarkson, 27 degrees from Dwight Heine, 27 degrees from Dwayne Johnson, 26 degrees from Tupua Tamasese Lealofioaana, 26 degrees from Stacey Milbern, 21 degrees from Sono Osato, 37 degrees from 乾隆 愛新覺羅, 27 degrees from Ravi Shankar, 30 degrees from Taika Waititi, 28 degrees from Penny Wong and 23 degrees from Chang Bunker on our single family tree. Login to see how you relate to 33 million family members.