KT-18, also known as "Kate," functioned as a housekeeping droid. Luke Skywalker acquired her at the Droidfest located on Tatooine, planning to present her as a housewarming present to his comrade, Han Solo.
During an incident where she was performing cleaning duties outside of Solo's sky house, KT-18 tumbled from the structure. Fortunately, Skywalker intervened using a cloud car and saved her before she crashed.