Hi Genseacher
i don't have much more information, I'm afraid. The O'Mahony book lists six other Whelans among the Dublin men in Frongogh - maybe some are related. They are:
George Whelan, 19 Russell St
James Whelan, 17 Upper Ormond Quay
John Whelan, 50 Marlboro Street
John Whelan, 9 John's Lane
Richard Whelan, Herberton Buildings, 23 Rialto Street
William Whelan, 31 Ballybough Road
The lists of Frongogh internees are in an appendix to the O'Mahony book. The only Whelan referenced in the book's index appears in a section on the arrangements for visits to the camp. Apparently prisoners were permitted one visit per month. The visits occurred on Tuesdays and Thursdays but were restricted to 15 minutes and were held in the presence of the camp censor, who ensured there were no complaints made and no mention of camp conditions . It seems, in spite of this, the prisoners used these visits for clandestine communications, getting Tuesday visitors to stay on in the locality to brief the Thursday visitors and with camp officers picking special prisoners for the visits to ensure these communications were most effective. The Whelan mentioned in the index is on a list of such priority prisoners. Unfortunately no first name is mentioned. Perhaps it was your grandad. My granduncles both lived at 7 Bessborough Parade, Rathmines.
Dermo