Hoping someone can help trace the marriage of the following people - Bernard Sullivan c1830 and Margaret Rush c1826.

Bernard is the son of Francis Sullivan and Lititia Morrison.
Margaret is the daughter of John Rush and ? McMahone.

I have them on the 1871 cen in Glasgow it says their first child was born there in 1856, although i cant find a cert for her. It also says Bernard and Margaret are from Ireland. I had hoped to find child,s birth to give me when and where they married as i dont know if it is north or south.

TIA
Christine