Maybe the Casey and Finnegan families were friends from 'the old country'? They could have kept in touch when they came to America via e-mail... er no... telephone... nope... heck, I'm not even sure the telegraph was widespread in those days!
She was born in Wisconsin because her mother came from Ireland to be a maid for a weathy family there. The family mystery is how did she meet her husband who is from Philadelphia.
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