mjlongeway:
Welcome back!
The 1901 census was taken on March 31st 1901 so someone born May 17, 1895 would be 5 at the time of the census. Derreennascooba is in Ballintober civil parish.
The parents were married in 1868 at the Burriscarra RC church . Below is a transcription of the civil marriage record. Thomas Kerrigan was the father of Michael and Patt O'Brien was the father of Kate. Here is the link to the parish register of Burriscarra. http://registers.nli.ie/parishes/1048 If they were baptized in that parish, you should be able to find the records for Michael and Kate. Records go back to 1839.
Roger McDonnell
Date of Marriage:30-Aug-1868
Parish / District:Balla district
County:Co. Mayo
Husband MichaelKerrigan
Wife KateO BrienAddress:Derrinascobe
Denomination:Civil Parish
Civil ParishOccupation:FARMER
Age:24
17Status:Bachelor (Previously unmarried)
Spinster (Previously unmarried)
Husband's Father
ThomasKerrigan
Wife's Father PattO Brien