I am also a St.John's and a relative told me that she was told a story from a family member that remembered going to visit "wellington St.John" in Hamilton and he was a butcher. That would be your relative. My relatives descend from Francis Perry (b: 1821) So I am thinking that he is brother to Harvey Nelson and Elizabeth Jane. From everything I have seen, no one has connected Francis. Francis states that he was born in the US, is Irish and that he is French. (I'm thinking Hugeunot)I am now trying to nail this thread down. (we have nelson's and harvey's in our line as well) This same relative that told me about your ancestor also told me that an ancestor said that they were very musically inclined and that a relative Stanley St.John played the piano at the eaton's centre in Toronto. And another was a big band leader in the 30-40's - that info is correct. This stanley is from Brock Township. His ancestor is a James St.John.b: 1818 (I think).
The info I have received is from a decendent of Benjamin St.John (Francis's son). She is an older woman and was searching for ancestors for 30 yrs and spoke to Charles Oscar's (Francis's son) son Harvey and daughter Bertha, before they died.
So... I would say we are probably related somehow.