What happened next is unclear but Hannah appears on the 1951 Census living in Cameron Street, Stonehaven as a widowed pauper with her 7 children. Husband William was born in Midmar and there are several Mathieson families living in the Parish of Fetteresso, so did Hannah move to Kincardineshire to be near his relatives? Unfortunately I have been unable to ascertain who husband William's parents were so cannot be certain.
I have not completely updated Hannah's profile on Wikitree but here is a link to it.