Napoleon calling the astronomer Lalande “grandpapa”
‘Bonaparte attends with great regularity the sittings of the National Institute, of which he is a member.’ ‘Bonaparte,’ he writes further, on April 20, 1798, ‘always calls me his grandpapa, because he is a pupil of D’Agelet, who again was a pupil of mine. I have begged him to use his influence with the Directory to obtain the removal of the Opera House, which in case of fire is dangerously near the Library. I also suggested the purchase of Paulmy’s admirable library, consisting of 100,000 volumes, and recommended that some new instruments and an increase of salary be granted to Thulis at Marseilles—all of which has been accomplished.’
*both of Napoleon’s actual grandfathers died young before he was born
Source: Life of Alexander von Humboldt (1872), Vol. 1, Pg. 233, Karl Bruhns (ed.), Jane Lassell (trans.) and Caroline Lassell (trans.)