Proper noun

Rhett leaning over the child had said: 'Her eyes are going to be pea-green.'

'Indeed they are not,' cried Melanie indignantly, forgetting that Scarlett's eyes were almost that shade. 'They are going to be blue, like Mr O'Hara's eyes, as blue as - as blue as the bonnie blue flag.'

'Bonnie Blue Butler,' laughed Rhett, taking the child from her and peering more closely into the small eyes. And Bonnie she became until even her parents did not recall that she had been named for two queens.