You are correct in showing the use of this passage to support the order of Mary's miracles. I used the chronological order of the miracles to show the saving of Willie as the first miracle. Dunstan does say that Willie's death is Mary's second miracle and refers to her saving of Joel (the tramp) as her first. That said, Dunstan also begins to think about Mary saving him from the snowball as a miracle when looking back on her life. If this is the case, then this would be her first miracle.

Like much of literature, interpretation is everything. In accordance with time, the saving of Willie (or the snowball) comes first. When Paul and Dunstan are talking about Mary being a saint, Dunstan says that her saving of Paul was her first miracle. It really depends upon if one is analyzing the chronological order of her miracles or Dunstan's numbering of them.

Mary Dempster, a character from Robertson Davies' Fifth Business, is responsible for three miracles in the novel. Her first miracle happens when Dunstan is required to baby sit his younger brother (Willie). The family had plans to go to the fair, but Willie became sick. Dunstan's parents go to the fair, leaving Dunstan to watch his sick brother. Over the night, Willie begins to get more ill. To Dunstan, Willie seems to have died. Dunstan runs over to Mary's house (where he husband keeps her locked up) and brings her back to his house. She brings Willie back from the dead (or so Dunstan thinks).

For her other two miracles, Mary "appears" to Dunstan in the form of a statue of Madonna (in front of a church) and she changes the life of a tramp by helping him find God.