In her earliest days on Earth, Supergirl lived at Midvale Orphanage under the name Linda Lee. In order to protect her secret identity, she created several robotic "Linda Lee" and "Supergirl" doubles to take her place at the orphanage when she went into action as Supergirl. After carrying out its mission, her robot hid out in a hollow trunk tree until it was needed again.
Once Linda was adopted and revealed her true self to Fred and Edna Danvers, she transferred several of her robots to Danvers' household's basement, keeping most of them stored in the Fortress of Solitude. Supergirl kept using her robots for several years until she graduated from Stanhope College and moved to San Francisco.
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