She was succeeded in the earldom by her grandson , Thomas , her eldest son Edward having predeceased her .
Lady Longford survived him by almost thirty years and died in January 1794 , aged 74 .
Lady Longford was succeeded in the earldom by Lady Longford 's grandson , Thomas , her eldest son Edward having predeceased her .
Lady Longford survived him by almost thirty years and died in January 1794 , aged 74 .