Hello mairindubh,
Edward Cassidy and Anne Marron had the following children, all born at Fartagorman:
Luke Cassidy b. 14 May 1865, Fartagorman
https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_retur…
Francis Cassidy b. 10 Jun 1867, Fartagorman
https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_retur…
Mary Cassidy b. 23 Mar 1869, Fartagorman
https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_retur…
Sarah Cassidy b. 19 Mar 1871, Fartagorman
https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_retur…
Edward Cassidy b. 13 Dec 1873, Fartagorman
https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_retur…
Bridget Cassidy b. 7 Dec 1878, Fartagorman
https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_retur…
1901 Irish Census: Residents of a house 4 in Fartagorman (Drumgurra, Monaghan):
Cassidy Edward, age 60, Male, Head of Family, Catholic, Widower.
Cassidy Luke, age 30, Male, Son, Catholic.
Cassidy Mary, age 30, Female, Daughter in Law, Catholic.
Cassidy Edward, age 7, Male, Grand Son, Catholic.
Cassidy Luke, age 5, Male, Grand Son, Catholic.
Cassidy Francis, age 3, Male, Grand Son, Catholic.
http://www.census.nationalarchives.ie/pages/1901/Monaghan/Drumgurra/Far…
Anne Cassidy d. 16 Dec 1878, Fartagorman, age 40. Married. Edward Cassidy present at death.
https://civilrecords.irishgenealogy.ie/churchrecords/images/deaths_retu…
Edward Cassidy d. 29 Jun 1905, Fartagorman, age 70. Widower. Luke Cassidy, son present at death.
https://civilrecords.irishgenealogy.ie/churchrecords/images/deaths_retu…
Luke Cassidy, full age, bachelor, of Fartagorman, son of Edward Cassidy married Mary Ward, full age, spinster, of Greaghnaroog, daughter of Francis Ward on 18 Jul 1893 at the Roman Catholic Chapel, Carrickmacross.
W. C. O'Doherty was the C.C., in the presence of Edward Cassidy and Ann Mee.
https://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_re…
Luke Cassidy d. 25 Jul 1906, Fartagorman, age 40. Married. Ned Cassidy son present at death.
https://civilrecords.irishgenealogy.ie/churchrecords/images/deaths_retu…
https://civilrecords.irishgenealogy.ie/churchrecords/images/deaths_retu…
1911 Irish Census: Residents of a house 4 in Fartagorman (Drumgurra, Monaghan)
Cassidy Mary, age 40, Female, Head of Family, R Catholic, Widow.
Cassidy Edward, age 16, Male, Son, R Catholic.
Cassidy Francis, age 12, Male, Son, R Catholic.
Cassidy Peter, age 7, Male, Son, R Catholic.
Cassidy Anne, age 5, Female, Daughter, R Catholic.
http://www.census.nationalarchives.ie/pages/1911/Monaghan/Drumgurra/Far…
Administration of the estate of Luke Cassidy late of Farthagorman County Monaghan Farmer who died 23 July 1906 granted at Armagh to Mary Cassidy the Widow.
https://apps.proni.gov.uk/WillsCalendar_IE/willsSearchResultsDetails.as…
After their marriage in 1902, Edward Cassidy and Bridget Duffy Cassidy went to Scotland, where they had three children in Edinburgh:
Births - Source: Scotland’s People:
CASSIDY, MARY HELEN, F, b. 1906, Ref: 685/2 365, St Andrew (Edinburgh)
CASSIDY, ANNIE CLARE, F, b. 1909, Ref: 685/2 147, St Andrew (Edinburgh)
CASSIDY, FRANCIS JOSEPH, M, b. 1911, Ref: 685/2 597, St Andrew (Edinburgh)
Baptisms - Source: Find My Past:
Mary Helen Cassidy – b. 27 Apr 1906, Baptised 6 May 1906, St Mary's Cathedral, Edinburgh.
Ann Clare Cassidy – b. 9 Feb 1909, Baptised 28 Feb 1909, St Mary's Cathedral, Edinburgh.
Francis Joseph Cassidy – b. 18 Aug 1909, Baptised 10 Sep 1911, St Mary's Cathedral, Edinburgh.
Possible Deaths - Scotland’s People:
CASSIDY BRIDGET, age 72, d. 1948, Ref: 685/2 296, St Andrew (Edinburgh)
CASSIDY EDWARD, age 84, d. 1957, Ref: 685/2 98, St Andrew (Edinburgh)
Scotland’s People is a $ site
https://www.scotlandspeople.gov.uk/
Find My Past is a subscription site (I'm currently doing the 14 day free trial with them)
https://www.findmypast.ie/
Your Longford letters may relate to Bridget Cassidy daughter of Edward and Anne!!
Hope this helps,
Maggie McKenna, Carrickmacross.
