According to her article in thepeerage, she married twice. Her first husband, Anthony Langley Swimmer, married only her while she was Sir Frances Vincent’s third wife.
Anton Rapahael Mengs portrayed many Spanish aristocrats so there should be a story about how Lady Arabella came to be portrayed by Mengs.
From history-of-fashion.tumblr.com. Also posted to the Reign of Louis XV - 1715 to 1774 Album here.
Lady Arabella goes to the masquerade in a spectacularly beaded dress with a stomacher adorned with ruched cloth ornaments arranged in scallops.
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