If you check the civil birth of Thomas the youngest 3rd May 1891
https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_returns/births_1891/02390/1891650.pdf it gives an address at 22 Queens Sq.
(unfortunately it now gives mother as DUNNE but the baptism image for St Andrews is online on Ancestry and that has the same DOB of 3rd May 1891.)
Workhouse records in 1893 show that both Richard and Christopher Byrne (aged 6 and 4) of 22 Queen's Sq entered the workhouse for medical treatment and were to be returned to their mother - a widow.
This looks to be Thomas Byrne (the father) death - same address 22 Queen's Square and he is listed as a stoker.
https://civilrecords.irishgenealogy.ie/churchrecords/images/deaths_returns/deaths_1891/06064/4728918.pdfRichard turns up in Workhouse records again in 1903 - a nurse child at a farm in Knockmitten with a Mary Tierney - it is found that he is "working with son on the land" and it is ordered that he be
returned to schooling.
I'd think that Mary has already died as well at this stage - so may be why Christopher gives brother Richard as NOK and not his mother when he joins the army.
All seems to fit - but no clincher !!
Is there an address for Richard in the Army records ?
EDIT - would have made more sense if I'd posted on the related thread
http://www.rootschat.com/forum/index.php?topic=771698.0