A gentleman in the upper reaches of his 'third age' begins dating a much younger woman, and after a time he asks her to marry him.
The woman accepts, and as they talk of the life they'll have together she says, "And who knows, dear, we might even have children."
"No, my love," he says, "my parents won't allow it."
"Your parents?" she says, astounded.
"Yes," he says.