The listed title for this is Hon. Emma Cunliffe, later Emma Cunliffe-Offley. Her birth date is not listed, but her younger brother was born in 1772 and Emma looks like a twenty or so year old. According to her article in thepeerage, she married Foster Cunliffe in 1809 so this portrait was done in 1809 or later. According to the article in theperage about her husband Foster, "In 1829 his name was legally changed to Foster Cunliffe-Offley when he assumed the name and arms of Offley."