He undertook to disparage my age when he himself had appointed his ten-year-old son.
Source, in full
Referring to the Emperor Macrinus and his declaration of his son Diadumenianus to be '"Caesar". The head of Diadumenianus was presented to Elagabalus as a trophy. As quoted in Dio's Roman History (1955), as translated by Earnest Cary, p. 439