Between the death of his father, in 1851, and the death of his grandfather, the 4th Earl of Rosebery, in 1868 he was known by the courtesy title of Lord Dalmeny.
Antara kematian ayahnya, pada 1851, dan kematian kakeknya, the 4th Earl, pada 1868, ia dikenal dengan gelar kehormatan Lord Dalmeny.