Wow, did I just say that?
In "Secret of the Ruby Reef," Kelli can be seen playing her guitar at a party being held at Alfea. She appears to be very skilled as her guitar-playing garners her a lot of attention from those around her, including Riven. He is so interested in her guitar-playing that Musa begins to take his interest the wrong way and gets angry at him.
In "The Pillar of Light," she observes the solar eclipse in the courtyard along with the other students.
In "The Singing Whales," Kelli is seen out on the courtyard and Musa catches sight of her walking away with Riven. This causes Musa to suspect that Riven may be cheating on her.
Kelli may know some basic, first-level spells that all fairies can use, such as telekinesis, transmuting objects, and fixing minor messes.