John Money suggested children might have awareness of, and attach some significance to gender, as early as 18 months to two years; Lawrence Kohlberg argues that gender identity does not form until age three.
John Money認爲孩子們可能早在年齡18個月到兩年之間就已經意識到並且認爲性別具有一定的意義，Lawrence Kohlberg認為，直到三歲時，性別認同才會形成。