Docter William Redmond

My great great grandfather was a docter in wexford in about 1870 his wife was sarah and they had a son john they moved to canada and america when john was a very young age. John was born in 1879 in wexford im trying to find any thing i can about william and sarah can any one out there help me if you can or know of how i can trace them l would love to here from you.