The only Martha I could see in 1891 is actually Martha Allen. The transcriber has carried on the name McGain from the previous family

3 Glenview Terrace
Thomas McGain 38 Railway Guard Malew
Isabella 39 Rushen [Watterson]
Annie 9 Rushen
Leonard R[obert]. 6 Rushen
Thomas A[rthur]. 2 Rushen

4 Glenview Terrace
Mary J. Allen wife 48 Lodging House Keeper Rushen
Rosa daur 21 Confectioner Rushen
Laura daur 16 Rushen
Annie N. daur 14 Rushen
Emerson D. son 11 Rushen
Charles S. son 8 Rushen
Martha A. daur 4 Rushen

Martha Amelia Allen 25 Apr 1886 Rushen, parents Edward Allen and Mary Jane Dawson (from Brian Lawson's births index).

If that isn't who you mean.....sorry.