Keady (in the parish of Maghera) is the next townland south from Ballynian. So John more or less married the girl next door.
Both were children of Laurence Margey and Rose Bradley
...wondering about your Rose Bradley, any idea of the townland that she was from?
On 4 July 1906 at St Patrick's RC Church, Glen.https://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_returns/marriages_1906/10134/5687091.pdf