In the Septuagint that verse does not mention children or women. It appears to have been changed to keep women suppressed.
The Septuagint was translated from Hebrew to Greek centuries before the Masoretes added their system of vowel points to the Hebrew text. The Septuagint’s version of Isaiah 3:12a (translated into English) reads: “O my people, your extractors strip you, and extortioners rule over you.”