I found a first marriage for Sarah Gladys Olive Charleton Jan 14, 1947 to John Robinson Glenn. Sarah was age 21 so born 1925. Father John Charlton, van driver which is correct. John Glenn was 38, resident Magherafelt, bachelor, father Charles, deceased school teacher.
Peggy13 not that this helps as to when Sarah Glenn nee Charleton married a Montomgery
you may have this information already but just in case you don't I thought I'd post
There are these
Glenn/Treanor Births
Magherafelt parents
Charles, occ School Teacher &
AmyCharles William Treanor Glenn 24 July 1906
Unknown Glenn (male) 6 March 1908
Baptismal name if added after Registration of birth
John Samuel Robinson Glenn 9 July 1908
https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_returns/births_1908/01670/1665163a.pdfSydney James Glenn 14 April 1909
Amy Gertrude Glenn 11 January 1911
Alice Mary Glenn 27 February 1913
3 in Grange (Desertmartin, Londonderry)
Glenn Charles 41 Head of Family Ch of Ireland Co Tyrone
N S Teacher Glenn Amy 29 Wife Ch of Ireland Belfast City N S Teacher
Glenn JACK 3 Son Ch of Ireland Co Londonderry
Glenn Sydney 1 Son Ch of Ireland Co Londonderry
Glenn Gertrude Daughter Ch of Ireland Co Londonderry
Lyle Rachel 37 Servant Presbyterian Co Derry General Servant Domestic
Married 5 years , 4 children born 4 living
Marriage
18 July 1905 Charles
Glenn 35 to Amy
Treanor 24,
both NS Teachershttps://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_returns/marriages_1905/10172/5700625.pdf