It's exciting to get a reply although I don't think the two stories match.My birth mum met Tom Fahy (she thinks this is the most likely spelling) when she worked at a factory near Birmingham which recovered reusable material from crashed aircraft.A lot of Irishmen came over at that time due to the labour shortage here after the war.Tom worked in the machine shop.The work there ended and he moved on down to London to stay with his sister (I would guess the sister was married).He wanted my mum to join him but as she was expecting me she was obviously in a difficult situation and decided to stay at home.Her Mum wouldn't allow any further contact from Tom and burned all his letters so we have no idea what happened to him after that.
My research in the BMD records in Dublin shows between 5 and 10 Tom Fah(e)ys born each year from 1918 to 1926.My birth mum remembers him mentioning the Shannon so I concentrated on the registration offices at Longford Roscommon Portumna and Scariff.Also I narrowed it down to 1923 to 1925 as she thinks they were both the same age.This leaves me with 3 possibilities.My next job will be to search for sisters a little older and look for their married names in London but it all starts to feel a bit hopeles with too many guesstimates.
The English records of deaths for Tom Fah(e)ys from 1973 to 2003 show 13 entries from the area of Manchester and nearby towns and 10 from London and its suburbs so it is tricky to pick one.
Anyway thanks for getting back to me and I hope your lost sibling starts to search soon and it becomes possible for you to contact her.
PS.Apparently my Tom was fond of quoting Yeats' poetry in Irish!