Did she have a daughter, Catherine, b. circa 1834?
There's an interesting household in Buckie on the 1881
Seatown, Rathven
Marquis Silverstone, 35, tailor employing 1 boy, b. Prussia
Catherine, wife, 47, b. Buckie
(Note - on SP indexed as Silverstine but looks like Silverstoni - possibly original ending was stein)
Also same place in 1901
Margaret's address on the DC was Seatown
Gadget