An actual baby A child The young gentleman A sweet girl (twelve) A chit A mere slip of a girl, with no right to dictate to me An errant schoolgirl! Still in the schoolroom Barely out of the schoolroom Green A schoolroom chit With the air of the schoolroom still clinging to her
What about "a faded spinster of indeterminate age," which is the age of every anxious governess?
A score years hence, we may add "Balzac-aged woman"
A fortune hunter is exactly my age, thank you
“A scrap of muslin.”