Hi sorry for my late reply on this been extremely busy with work however this may help you out
William Quan and Catherine Brennen where married in Powerstown Clonmel on the 04/02/1838 I have their marriage cert.
Based on information gathered locally I was told that William Quans father was called Maurice Quan I cant find a record of this link yet, but this guy Maurice was hanged from the old bridge for breaking into a house in Tinhalla Carrick on Suir with 4 other guys he was the only one hanged for this the others where deported to Australia, the information on the court case is on the internet I have found several web sites that document it.
Its also said that the Quans have a link to Thomas Frances Meagher I know his mother was Alicia Quan but I cant make the link I am pretty sure if you go back far enough you would find it as Quan is not a popular name in Waterford/Tipperary so its possible they are all related.
John Hyland married Mary Carey in 1866 and had a 2nd class house which consisted of 7 rooms which would have been a large house at this time, I can say they had 4 children but there may be more, Michael, Johanna, Denis and James, there may have also had a son called William or Richard but I cant say for definite
Denis died in 1889 aged 9 from epilepsy
Michael was a R.I.C officer
James was also a R.I.C officer, his son Richard died in 1929 aged 16, his 3 other sons became priests Joe, Frank and William, there was also 2 daughters Shelia and Mary
The Hylands came from Coleman clonmel
Mary Carey Hyland died in 1887 aged 49 I have her death cert
3 of the Tanglers sisters where nuns I have photos of them and 1 brother a priest I also have a photo of Michael Murphy and Ellen Quan,
There is a lot more information that I have however I have passed it all on to my uncle as I am helping him to but it in book form
If there is anything you can add or find some link with the Quans that would be great but for now I shall keep digging myself