Lord Clifden's only son George James Welbore Agar-Ellis was created Baron Dover in 1831 (see below), but predeceased his father.

[1] On his death, the barony of Dover became extinct, while he was succeeded in the other titles by his kinsman the second Baron Robartes, who became the sixth Viscount.

The sixth Viscount had earlier represented Cornwall East in Parliament as a Liberal and also served as Lord Lieutenant of Cambridgeshire from 1906 to 1915.

Thomas Agar-Robartes sat as Liberal Member of Parliament for Bodmin and St Austell, but was killed in the First World War, predeceasing his father, unmarried.

He sat as a Liberal in the House of Lords and served as a Lord-in-waiting (government whip) from 1940 to 1945 in the war-time coalition of Winston Churchill.

Agar-Ellis represented Heytesbury, Seaford, Ludgershall and Okehampton in the House of Commons and served under Lord Grey as First Commissioner of Woods and Forests from 1830 to 1831.

On Lord Dover's early death in 1833, the title passed to his eldest son, the second Baron.

His mother was Anna Maria Hunt, great-niece and heiress of Henry Robartes, 3rd Earl of Radnor (whose titles became extinct in 1757).