Thankyou very much Sandra for all this research, but it has confirmed that this is not the same family that I had hoped it was. Mine is a Margaret Oswald born scotland 1853 (nee king) with daughter Helen (registered as Mary) born scotland 1889. I have found them in the 1901 & 1911 scottish censuses but not in the 1891 one.
Thanks
Silvercraig