If you think Thomas/James Keenan was a soldier have you searched for the military records?
I have found this record but do not know what the regiments etc was and if there are records available. Trouble is that he could not be the father of anyone born after Sep/Oct 1832.
Name: James Keenan
Gender: Male
Burial Date: 11 Nov 1831
Burial Place: Mhow, Bengal, India
Age: 28
Birth Date: 1803
Occupation: Gunner, 3 Co., 1 Batt.
Marital Status: Unknown
Mhow was founded in 1818 by John Malcolm as a cantonment town. It is still a major location of the Indian Army.FindMyPast has a good collection of military records, you might find this James Keenan there and be able to eliminate him, or not!