Lady Mary MacDonnell daughter of Randal MacDonnell, 1st Earl of Antrim (b. 1610) Parents Ellis MacDonnell, Countess of Antrim Randal MacDonnell, 1st Earl of Antrim Children Theobald Dillon, 3rd Viscount Dillon of Costello-Gallin Matthew Plunkett, 7th Baron Louth Siblings Alexander MacDonnell, 3rd Earl of Antrim Randal MacDonnell, 1st Marquess of Antrim Lady Sarah MacDonnell Lady Rose MacDonnell Lady Alice MacDonnell Lady Anne MacDonnell Lady Catherine MacDonnell Partners Oliver Plunkett, 6th Baron Louth Lucas Dillon, 2nd Viscount Dillon