Not sure if I'm onto something or not but just in case it can help...
Starting with this newspaper snippet-
Frontier Sentinel, 24 Apr.1926: Mr. J. MAGEE, Newry. The remains of the late James Magee, Lower Water Street, Newry, were removed for interment in the “Old Chapel” Cemetery, the Rev. E. Campbell, … officiating. The chief mourners were- Margt Magee (widow); Elizabeth C. Magee (daughter) …
I found the birth of that daughter and was able to work back. However, several conflicting bits of information came to light (deceased also called John and wife was Mary- could OCR have inserted Margt for Mary?)
Elizabeth Catherine Magee, daughter of John Magee & Mary Conlon, born 4 Oct.1915 at 109 Canal St., Newry-
https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_returns/births_1915/01363/1562098.pdfNote: all the births listed below also show mother's maiden name as Conlan.
Then I searched for other children of the couple and found these-
Gertrude Magee born 27 Nov.1904 at 109 Canal St.-
https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_returns/births_1904/01809/1708921.pdfDied 24 Apr.1909 at 1 Barrack St.-
https://civilrecords.irishgenealogy.ie/churchrecords/images/deaths_returns/deaths_1909/05464/4529336.pdfWilliam Henry Magee born 27 Apr.1908 at 1 Barrack St.-
https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_returns/births_1908/01659/1661788.pdfJames Herbert Magee born 25 Jan.1911 at 1 Barrack St.-
https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_returns/births_1911/01543/1624942.pdfUsing the address from the 1911 birth I was able to find the family a few months later in the 1911 census-
https://www.census.nationalarchives.ie/pages/1911/Down/Newry_West_Urban/Barrack_Street/254292/All listed as Church of Ireland and James Magee born Co.Down. Married 8 years, 3 children/2 living (deceased child is eldest, Gertrude)
After quite a bit of searching I found the marriage-
John Magee to Mary Connolly-
https://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_returns/marriages_1903/10244/5728300.pdfJohn's address is 109 Canal St. (daughter Gertrude born there in 1904 and Elizabeth in 1915). An Emily Magee shown as a witness. John's father called Alexander Magee, carpenter, so does this and 1911 census saying John born Co. Down rule out this one?