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Trying to find details on the Marriage and so on of Robert James Cregan showing on 1911 census living in Queensland Ballyvoloon .....
It's actually Ballyvoloon townland, in the electoral district of
Queenstown - now called Cobh.
Mary Anne and the children are all born in Co. Cork so that looks like the best place to search for a marriage.
This looks like a good match from the BMD Index :
Name: Robert James Cregan
Registration District: Cork
Event Type: Marriage
Quarter and Year: Jan - Mar 1901
volume Number: 5 / page : 137
here's a link for reference :
Cregan Family 1911 censusShane