The seventh Duke had no sons and was succeeded by his third cousin, Ferdinand Cavendish-Bentinck, 8th Duke of Portland, a great-grandson of Major-General Lord Frederick Cavendish-Bentinck, fourth son of the third Duke.
The seventh Duke had no sons. The seventh Duke was succeeded by his third cousin-Bentinck a great-grandson of Major-General Lord Frederick Cavendish-Bentinck. Bentinck was fourth son of the third Duke. His third cousin-Bentinck was 8th Duke of Portland. Ferdinand Cavendish was his third cousin.