Kallie Calwell was the daughter of Dannar and Annileen Calwell, both Human Merchants hailing from the Pika Oasis. Furthermore, she was the sibling of Jabe Calwell.
When Kallie reached the age of nine, she was given the responsibility of caring for the Calwell family's dewbacks.
Kallie was still occupied with her family's dewbacks in 19 BBY. While riding a dewback named Snit, the creature bolted and ran toward the Rumbles, which housed one of Tatooine's sarlaccs. Her mother, Annileen, attempted a rescue mission. It was at this moment that Obi-Wan Kenobi arrived to assist the teenager before they plunged into the sarlacc pit.
Kenobi rescued both Kallie and Annileen, but the sarlacc devoured the dewback, Snit. Annileen, who had been rendered unconscious when Kenobi used the Force to throw her off the dewback, informed Kallie that the cost of replacing the dewback would be deducted from her earnings.
Following this event, Kallie recounted the tale to others at the Pika Oasis.
Three days later, Kenobi paid a visit to the Oasis to purchase feed for his eopie, Rooh. Kallie was assigned the task of gathering the feed, while her mother escorted Kenobi on a tour of their shop. Upon returning to the building, Kallie launched an attack on Veeka Gault and subsequently shadowed her mother to observe Kenobi's departure.
Later, she was present at the Comet Run Podrace held at Mos Espa.