Lets go back a stage
You are confident that Sidney Pashley and Mary, are your ancestors?
And you have their marriage cert, in Sheffield, in 1851?
Who does she name as her father? and his occupation? And how old is she? Her address? And witnesses names?
Lets be sure the 1841 family is right! Especially as only one census she says bn Sheffield (and that is when she is with inlaws, so they probably filled it in and put Sheffield like everyone else in the house), when it is her and Sidney she puts London on several censuses.