I'm not sure. I don't remember my Grandparents mentioning the name Martha. I have a small history of the family that my grandparents gave me. My Grandfather was Samuel Alexander Mercer and he had a brother Robert Mercer that moved from Chatham Ontario and lived in Victoria B.C.. My Grandfather's father was named Robert and Robert's father was named John. Samuel and Robert had a sister Catherine. The family was from England ' I can send you what I have. John settled in Chatham around 1833 and was the first sheriff of Kent '