Although he was highly successful in his business, Ramsden does not appear to have been so successful with his marriage for his wife did not move with him when he opened larger premises in 1773. Sarah and their son John moved into a house owned by the Dollond family, but Sarah seems to have continued to assist Ramsden in his business.
Kahit na siya ay lubhang matagumpay sa kanyang negosyo, Ramsden ay hindi lalabas upang sa gayon ay matagumpay sa kanyang kasal sa kanyang asawa ay hindi ilipat sa kanya kapag binuksan niya mas malaking lugar sa 1773. Sarah at ang kanilang mga anak na lalaki ni John inilipat sa isang bahay na pag-aari ng Dollond pamilya, ngunit tila Sarah na magkaroon ng patuloy sa pagtulong sa Ramsden sa kanyang negosyo.