Hello Roger,
I did find my John, turn out that he did emigrate.
If I compare the two census records of 1901 and 1911, I'm able to see that John James Doyle moved to England, seem with his older brother. I see as per the 1911 census that there were 9 children between Thomas and Mary.
There is a discrepancy between his birth date however wither 1882 or 1883. I have uploaded the census records from England and see at 19 he was a farm labourer and a teacher at age 29. I'm 100% certain that the data from 1911 is correct. Are you able to share the link with me where you foudn his baptism record, I am unable to find it. I also know he was born on the 20 July, but the question is still year of birth 1882 or 1883. I'm hoping that the parish/ baptism record you found could help me?
http://www.census.nationalarchives.ie/pages/1901/Carlow/Ballymoon/Gormon...
http://www.census.nationalarchives.ie/pages/1911/Carlow/Ballymoon/Gormon...