Searching for William Flynn

Just returned from visiting County Cork and meeting new cousins- Thanks to Ireland Reaching Out and the wonderful Kieran Jordan! Now on the hunt for the other branch, that has taken me to County Limerick and Monagea. I have a marriage of a Thomas Flynn in 1837 and another marriage for him in 1842, at the same place. First to a Joanna Kearns, then to a Joanna King. I believe that a son William was born around 1838-41, but have had no luck. They have arrived in Merthyr Tydfil, South Wales and are shown in the 1861 census with sons William (1841) and James (1844) who are born in Ireland. William is shown as 83 years old (1838) in the 1921 census.

Looking to connect with this part of Ireland next. Is there someone in Limerick that is able to guide me and perhaps signpost me to finding the mysterious William.

I have convinced myself that Joanna Flynn nee Kearns died when William was very young and that Thomas the father married again to another Joanna nee King!! Happy to be proved completely wrong!!!

William is my wife's x2 great grandfather on her mother's fathers side of the family. Looking forward to some news and perhaps lay the foundations for another visit later in the year.