According to her article in thepeerage she was a Countess before she married and acquired another County.
The collection that includes this is probably at Leslie House, in Leslie, Fife.
This double portrait shows how 1600s male and female fashion mirror each other. The Earl has nothing to gain from an off shoulder neckline, but the Countess has something to show.
Keywords: Wright - John Michael, Leslie family, Hamilton family, British, curly coiffure, off shoulder scoop neckline, chemise, modesty piece, elbow length puffed under-sleeves, split bodice, elbow length puffed over-sleeves, slashed sleeves, girdle, vee waistline, full skirt, necklace, earrings, clasps, wrap