Dower/Wallace Families in Waterford

Hi i am try to research my Dower/Wallace families.

My Great Great Grandfather was John Joseph Dower born in Waterford in 1879. He married a Florence May Hookway and died in Plymouth 1950

His parents are John Dower and Margaret Wallace.

I believe Margaret's parents are Thomas Wallace and Johanna Gormon according to her birth records.

Thats where it stops. I am struggling to find Johannas birth records, if any. While Thomas Wallace, there are so many i dont know which one to go by.

As for the Dowers the same story as there are so many John Dowers back then aswell.

I have looked at irishgenology and not much is coming up that i can see, while ancestry is showing a bit more but not the ones i believe are mine.

Any ideas? Could someone help me please?

Thank you in advance

Michelle