I can't figure out the connection but my great-great grandfather Innocenzio Papa was also an ice cream vendor in Islington. He moved to London from Italy in the later 1800's with at least half a dozen kids from his first wife and remarried there to a woman named Sarah Houston with whom he had about a dozen more children.
I believe his brother's name was Glorio Papa who also lived in Islington.
Papa is one of those common names but perhaps we can figure out what the mutual link is.