Mary, Countess of Inchiquin (1750–1820), by Thomas LawrenceMary O'Brien (née Palmer), Countess of Inchiquin, by Thomas Phillips after original by her uncle Sir Joshua Reynolds, Petworth House, Sussex.Mary O'Brien (née Palmer), Countess of Inchiquin, painted before 1785 by her uncle Sir Joshua Reynolds. Collection of Fairfax House, City of York
Mary Palmer (1750 – 6 September 1820) was a member of the British gentry and by marriage of the Irish peerage.