"I want my own sort!" It literally made me bound forward. "There are not many of your own sort, Miles!" I laughed. "Unless perhaps dear little Flora!" "You really compare me to a baby girl?" (14.12)
Ah ha – finally we see Miles betray some inner tension. While the Governess rather naively thinks that Miles and his sister are equals because of their birth and status, Miles's bitter reply shows that he rates them on different levels – by deriding Flora as a "baby girl," he claims superiority not just by age, but by gender.