Stellar was a six-year-old girl who was shopping with her mother on Iceworld. She and her mum were among the few survivors on that planet. Her mother was a customer who got an ice cream tipped over her head after annoying Ace in Iceworld's ice cream parlour.
When Stellar lost her mother during the chaos created by the mercenaries, she came across the dragon, put her teddy bear to bed in Kane's freezing chamber and had a little giggle when she saw the TARDIS vanish. (TV: Dragonfire)