On 02 Dec 1790 John Bourke 1st Earl Mayo (age 90) died. His son John Bourke 2nd Earl of Mayo (age 61) succeeded 2nd Earl Mayo, 2nd Viscount Mayo of Monycrower in Mayo, 2nd Baron Naas of Naas in Kildare. Mary Leeson Countess Mayo (age 56) by marriage Countess Mayo.

On 20 Apr 1792 John Bourke 2nd Earl of Mayo (age 63) died. His brother Bishop Joseph Bourke 3rd Earl of Mayo (age 56) succeeded 3rd Earl Mayo. Elizabeth Meade Countess Mayo by marriage Countess Mayo.