The 1901 census provides some information. Mary's maiden name was Gorman and John's fathers name was John.
I looked for a civil marriage index record around 1896-1897 with no success. i did look at the indexes for Roots Ireland www.rootsireland.ie and found that they were married in 1897 in the Kinvara RC church.
By working the indexes, I figured out that her father Mary's father was John Gorman. Roots is a pay site to view the transcription of the church record.
I looked at the 1901 census further and found this record in the parish. Possibly, it is Mary's family.