John Grady & Ellen Page, Keyfield

Thomas's older brother James of Keyfield has a son, John, who married Ellen Page:

https://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_returns/marriages_1913/09900/5597406.pdf

Included the Michael Waldron/Winifred Grady marriage above it too, as that is John's first cousin.

They have a son, James, in 1915:

https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_returns/births_1915/01374/1565838.pdf

Note: included Waldron birth from Keyfield too ... chances are, they are related.

James moves to Salford in the UK, and marries Janet McApline in 1940.

He also joins the army in 1940, serves in North Africa with the Durham Light Infantry, 6th Battalion, and takes part in the invasion of Normandy, June 6th, 1944:

https://www.findagrave.com/memorial/56498522/james-grady

Good website on the Durham Light Infantry, although nothing specific about James:

https://durhamlightinfantry1920-46.weebly.com/

It is interesting that this branch of the family sticks with just 'Grady' without the 'O' prefix.