firstborns tend to be less clever
Proverb suggesting that the eldest child, often overprotected, may lack worldly wisdom or initiative.
They say 'the eldest is the least clever,' but our firstborn is quite capable.
The exact origin is uncertain. 総領 (そうりょう) means the eldest child or heir, and 甚六 (じんろく) is a name used here to imply a simple or dull person.