Dan,
It seems we may just have a remarkable coincidence...but I'd like to explore it further, for to find two sets of brothers with the same names in a small town (?) like Midleton at the same period and with a similar military history is odd.
I have John Myles' army papers which showed him to be 24 years of age when he joined up in 1898, so born about 1874. As I said before his next of kin was shown to be his mother, Maria Myles. There was also a note on his papers that he had two brothers also serving, William in the 1st Battalion, and George in the RHA. John was also in the 1st Battalion. I could not find a birth cert for John, but I did find one for William born on 10th Dec 1875 in Thomas St, Midleton, his parents being John and Maria (nee Burchill) Myles. Their sister Annette was my Great Grandmother, and she stated on both the 1901 and 1911 censuses that she was born in Wicklow in about 1870 but the date varies over several different records.
My mum told me that Maria's marriage to John was her second marriage, and I don't know anything about her first marriage, or even if the name Burchill was her maiden name or that of her first husband.
I also have William's marriage cert to Margaret Wallace (1903) in St Peter's church Dublin, his father again shown as John. You'll find him on the 1911 living in Molesworth St, Dublin. I also have his army papers which are nowhere near as detailed as are John's, but show Midleton as his place of birth. He served in the Boer War too, but only for a short period. His name is not on the medal roll for the Queen's SA medal although John's is and with various bars attached for the actions he took part in.
Of George I could find no birth cert, so don't know his year of birth, but there is a George Myles living in Cork City in the 1911 census, married with two children, and that could well be him.
I have never heard of Alec.
Here's the picture then (hopefully!) in his red coat.