Hi Michael - here is the baptism record of Denis showing the names of his parents. I hope it's the right person.
Ireland, Catholic Parish Registers, 1655-1915
Name
Denis Higgins
Baptism Age
0
Event Type
Baptism
Birth Date
1810
Baptism Date
2 Jul 1810
Baptism Place
Stradbally, Waterford, Ireland
Parish Variants
Ballylaneen, Stradbally and Ballylaneen
Diocese
Waterford and Lismore
Father
Denis Higgins
Mother
Bridget Dun