We know very little about Sister Winifred Kelly's background or early family life, how and where she was educated, or how she met the Adrian Dominicans.

We do know that on June 7, 1868, she was born in the "Thumb" of Michigan, on a farm in Delaware Township, Sanilac County. Baptized Sarah Ruhamer Kelly, she was always called Sadie. According to her birth certificate, her parents were Elizabeth Kelly from England, and Isaac Kelly from New York; her mother's maiden name, however, may have been Ruhamer. The Kellys were among those who sought good farmland, and found it in the "Thumb" where they built their home and farmed the rich soil.

Sadie may have met the sisters ministering at Port Austin, Gagetown or Ruth, or perhaps been directed to Adrian by a priest-friend. When she entered the postulate at Adrian in 1912, she was forty-four years of age, and she received the habit and her religious name on December 27. As a novice, she was sent to Illinois with the sisters who opened Ascension School in Harvey. After profession on December 30, 1914, she taught at St. Patrick School in Joliet, Illinois, where the Adrian Dominicans replaced the Ladies of Loretto.

Sister Winifred's health was delicate, and it was in Joliet that serious signs of tuberculosis appeared. Suffering from severe pain in her chest, she was taken back to Adrian, where she was treated in one of the two white houses that served as infirmaries. She lived only a short time after reaching Adrian, however. On July 16, 1915, a little more than six months following her profession, God took her to eternity at the age of forty-seven.

After Sister Winifred's death, there were assertions that she had "come back" and that she had been seen in various places. Some of the novices recreating on the St. Joseph Academy playground in the evening declared that they saw her; someone claimed that at noon one Saturday she was on the church steps of Ascension Church in Harvey, Illinois; and a rumor circulated that she had appeared to Sister Augustine Walsh, who was then novice mistress.