I'll PM you Brigid
As far as I've got back is
William George Quin, born c 1845 in Dublin
married in January 1865 in Birkenhead:
Mary Ann Jones, born c 1837 in Wepre (which is close to Connah's Quay, Flintshire)
Their first child (that I know of, haven't searched GRO) Caroline Winifred Quin was born in December 1870 in Sparkbrook, Worcestershire, but by the 1871 Census the family were back in Birkenhead where William George was a 'marker at the docks'.
Second child William George Quin (grandfather of Ethel/Iris Quin) was born in 1874 in Birkenhead.
I believe he was in Essex on a ship, the Countess of Durham out of Sunderland, as a fireman in the 1881.
In the 1891 he's back in Birkenhead, a mariner, shopkeeper.
And I believe he died in 1900.
I've not researched William George senior any further in Ireland, the Dublin reference is the only one I found to the location of his origin.
Don't know if that helps at all with your Quin/Quinn family