Solaria/Series

Season 3
Stella's father, Radius, is seen a lot this season.

In the first episode of this season, Stella receives a sun gram from her home planet, the messenger announces Stella's official Princess Ball.

Then, in the next episode, Stella and Bloom head to Solaria first and there Bloom meets Stella's father and Stella shows her around the castle. Once that was done, she shows Bloom a room full of gifts for her princess ball, unbeknownst to them, Chimera was spying on them and has already despised Stella from the very beginning. Countess Cassandra scolds Chimera for her unlady-like behavior in terms of snooping but also despises Stella. Valtor sees this and decides to appoint them as his accomplices.

After agreeing to show him the Second Sun of Solaria in exchange for more potent powers, Countess Cassandra and Chimera lead Valtor to the place where the it is kept. He then steals the energy of the ever-shining magical sun of Solaria to restore his power. He caused the weather of just sunshine into rain and clouds. The princess ball was quite a wreck, with Stella becoming a monster, thanks to Chimera's spell, and now her father is under Countess Cassandra's control.

Over the course of the season, Solaria was being run by the Countess herself and the King, barely making any effort to control the situation due to Cassandra's spell. Solaria almost had a new queen until Stella, alongside the rest of the Winx prevented it from happening. Stella also frees her father from Cassandra's spell bringing peace once more.

When the Winx defeat Valtor, the energy that was stolen got rid of the rain and the sun came out once more.

Season 5
Tritannus visited Solaria, after taking Illiris's powers and entering the Ocean Gate from Andros. After Stella figured out that the Gem of Self-confidence is somewhere in the Royal Deeps, the Winx came to the Oceans of Solaria to find it. They soon met a selkie called Illiris, who is the gatekeeper of Solaria. It is here where Stella bonds with Illiris, restoring her powers that Tritannus took from her. They then go into a cave where they face a mutated jellyfish which has been under Tritannus's pollutions influence. It turns Flora into stone, however Stella finds a shield with the Gem of Self-confidence and uses it to reflect the "stone look" back to the jellyfish, turning it into stone. She then uses the shield again to break the curse from Flora. After taking the Gem of Self-confidence, all the Winx acquire it into their Sirenix Boxes.

In the episode "The Eclipse", Solaria appears again as the planet's Second Sun begins to fade due to the stolen seal of Pillar of Light. This dimming and loss of strength of the Second Sun rapidly weakens Radius as his life force is tied to it. It is also the first time Queen Luna appears, she comes to the Castle of Solaria, worried for her ex-husband's health. She stayed to care for him while the Winx take of Tritannus in the Infinite Ocean. The pillar is then restored by Stella because she thought of her parents.

Radius is now back to normal and when Stella arrives at Solaria she is anxious that her parents will begin to fight again. She enters the palace's conference room and there are her parents, they express their gratitude and appreciation for what she had done. But, when Stella voiced that she thought of both them and put them together in order to restore the pillar, though Luna was very happy hear of it, Radius on the other hand was not. They continue to argue with both of them leaving the room angry, which upsets Stella to the point of tears.

Season 8

 * Winx Club - Episode 817