“I am old, Peter. I am ever so much more than twenty. I grew up long ago.”
“You promised not to!”
“I couldn’t help it.”

J. M. Barrie (1860-1937) Scottish novelist and dramatist [James Matthew Barrie]

Peter and Wendy, ch. 17 “When Wendy Grew Up” (1911)
    (Source)

Wendy speaking to Peter, who has returned many years later, though he is unaware of the interval.