He succeeded to his father 's titles in 1793 .
Ponsonby was the eldest son of Viscount Duncannon ( who succeeded as the 2nd Earl of Bessborough in July 1758 ) and Lady Caroline Cavendish , daughter of The 3rd Duke of Devonshire .
Ponsonby succeeded to Ponsonby 's father 's titles in 1793 .
Ponsonby was the eldest son of Viscount Duncannon ( who succeeded as the 2nd Earl of Bessborough in July 1758 ) and Lady Caroline Cavendish , daughter of The 3rd Duke of Devonshire .