Early in Portal 2's development, while Mel was still the main playable character, with Cave Johnson serving as the main antagonist, Betty would introduce the player to each chamber in a similar manner to the one used by GLaDOS during the events of Portal. Betty was to "roll out after [Cave Johnson] had described the test," and give a disclaimer that would bar Aperture Science of any responsibility for the potential dangers encountered during testing. Betty's early model was a small Morality Core attached to a lamp from Half Life 2.
- Betty's associated acronym (GLAaDOS) was to be the only reference to the original character in Portal.
- Portal 2 - Post Mortem (GDC) on Youtube