Although she might disagree with her friends, Stella is very supportive and protective and will not hesitate to help them. She learns to accept that love and friendship are far more important than royalty, fashion and shopping. Sometimes she hides her true personality because of her upbringing. However, she has finally managed to uncover it in the 4th episode of season 3.
She has always wanted her separated parents (King Radius and Queen Luna) to reconcile, to the point that she was angry that her father, King Radius, announced his marriage to a new woman, Countess Cassandra, mostly because her daughter Chimera had been mean to her.
Stella is generally on good terms with Bloom. She was the one who first introduced Bloom to Alfea, and also comforts Bloom whenever the latter is stuck in a seemingly hopeless situation. She may not be not as close to the other Winx Club fairies (and might even annoy Musa due to their all-too-vastly-differing personalities), but she truly cares for them as well and remains good friends with them all.
Stella sometimes flirts with other boys, but she still loves Brandon wholeheartedly. Stella believes that he's the best boyfriend in the world and sometimes brags about it. Bloom is considered to be her best friend in the club. Her bonded pixie, as shown in the second season, is Amore, the pixie of love.
In this season, Stella brought Bloom to Alfea when Bloom discovered her magical abilities. She forms a team, Winx Club, with four other girls, Bloom, Tecna, Musa and Flora. Together, they fought evil and brought peace and harmony to Magix. At first, the three witches, Icy, Darcy and Stormy attempted to steal Stella's ring, as they believed it had the power of the dragon. They sent a note pretending to be Brandon asking her out on a date. At last, they succeeded, by kidnapping and binding Stella and thus forcing Bloom to hand over the ring. (It came to Bloom's possession as Stella had chosen to wear another ring for her date, but this turned out to be false) and immediately tested the ring for its magical powers. However, they were disappointed that the ring was not as powerful as they had expected.
During the period Bloom took to adapt to the new environment, Stella offered sympathy and comfort when Bloom faced setbacks. One example was when Bloom knew Sky's real identity and was heartbroken. Stella consoled and comforted Bloom, even though she was in the same predicament. As a result, Bloom is grateful to her.
Stella's relationship with the three other girls grew as they went on their missions to fight evil. They started to gain deeper understanding and trust in their friends, and appreciated their friends for their different personalities.
Stella and Brandon also started to be interested in each other. This was because they had the same interests, namely shopping and fashion. Initially, Stella knew Brandon as Sky, but in the 17th episode, when Sky's true identity was revealed, she was horrified to realize that he had lied to her. She was devastated, just like Bloom, but she was optimistic and cheerful, and recovered from her shock. Perhaps Stella truly loved Brandon, so she accepted him as a squire.
Stella aided Bloom in recovering her power when the three witches stole it to dominate the world. Eventually, Bloom recovered her powers, and Stella and the others joined the battlefield. Stella, Flora, Tecna and Musa held off Darcy and Stormy, whereas Bloom settled a score with Icy. In the end, the Winx Club emerged victorious.
Stella's Winx outfit contains of a sparkling orange top and mini-shorts, with knee-high boots of the same color. She wears her hair in two pigtails with orange tube ties. She also wears light blue tube wrist bands and a headband of the same colour. Her wings are three leafets with the colour of powder blue with teal tips. Her Charmix is a mirror-shaped pin and a round waistbag divided into the sun and moon. Stella earned her Charmix by apologizing to Layla/Aisha.
Her Enchantix outfit is primarily orange, with turquoise blue and pink trimming, pink translucent gloves , big and ample blue butterfly wings with deep chrome yellow outlining. Her pigtails are now styled higher upon her head, her hair grows in length and seems to earn a few bleach-blonde highlights and is brighter in contrast to her traditionally sunlight colored hair. She has also discarded her orange colored boots and dons strappy barefoot sandals connected by a sideways crescent button. She wears a turquoise colored tiara upon her head. Her fairy dust bottle is a yellow diamondized one surrounded by two orange stars with the outer one having jewels on it.
Stella was the second to obtain her Enchantix in episode eight of season three, after sparring off against a rampaging dragon to protect her father during a party on Prince Sky and Sky's home planet, Eraklyon.
Stella's transformation sequence is short but very detailed and interesting. Firstly Stella twirls around into a pose and a green flash comes from behind her. Stella's wristbands, boots and main outfit then form in flashes of golden light. Then she screams and twirls back and orange ribbons come flying wrapping around her hair creating her pigtails, she then skips down into her finishing pose light comes behind her.
Stella's attacks are mainly based around light and heat, which can be explained by her connection to the Sun. Stella can throw blasts of sunlight energy and can make balls of solar heat. She has also used an attack called sun burst which burns things. She can concentrate her energy to make herself glow brightly in dark places. Stella can create streaks of solar energy and is able to create explosions of sunlight. She can shape sunlight into barriers and shields. She can conjure light in any area, no matter how dark. Due to Stella being from Solaria, she is majorly affected by the sun. She gains her energy from the sun and is heavily weakened when in very dark places or underground. It is stated that Stella is also connected to the Moon, but only two attacks have appeared representing this: Enchantix Moon Shield and Lunar Magnetism. Stella also has the ring of Solaria and which conveniently transforms into a magical scepter when needed. This ring allows her to focus on her energy or teleport people. However, after the sixth episode, in which she takes the ring back from The Trix who stole it in the previous episode, the ring has only made a handful of appearances since.
Stella's Enchantix transformation sequence is long and extremely detailed. First, she spins around and her tiara comes on, her eyelids turn orange, and her pigtails grow. Second, Light comes over her body and she puts her arms out one by one so her translucent gloves can come on. Then, her top flies onto her she turns to left to let the star on her chest form. After that, she flies up and her skirt comes on. She then flexes her legs and her sandals come on. Afterward, she flies and her wings come out. She opens her eyes and then blows a powdery heart-shaped kiss, before striking her final poses.. She is the 2nd Winx Club member to earn her Enchantix.