In her debut episode The Boy, the Starfish Grandmother comes to the Starfish Palace for a visit, but by the time she arrives, the Starfish Queen finds Spikey sleeping in Ester's bed, with the princess having already gone with Polvina and Tubarina to help Leia free a beached whale. Upon her return, Ester tells her grandmother about her adventure, asking her to keep it a secret (which she loves).
In The Runaway Grandmother, the Starfish Grandmother returns for Salacia Day. Every year since Ester was born, she gave her a red beanie on Salacia Day, but unbeknownst to her in recent years, Ester believes that it is totally uncute and decides to "lose" the beanie on purpose; she didn't say anything to her grandmother because she didn't want to hurt her feelings. On that day, however, when her granddaughter unexpectedly meets her on her way to the fair, Ester blurts out her true feelings about her beanie, leading the Starfish Grandmother to return home, where on the way, her scarf was swept away by the sea current and was caught on a cliff into the Abysmal Kingdom. When Ester meets her again later, after having thought she had fallen into the Abysmal Kingdom, the Starfish Grandmother says that she was getting tired of knitting beanies anyway, to which Ester says that she likes them again after a beanie saved them. She gives Ester another red beanie, having already given hers to an anglerfish who liked it, along with extras for Polvina and Tubarina, much to the latter's chagrin.
Returning for a final time in Beauty with her pet starfish Pointer, the Starfish Grandmother tells the Starfish Queen about knotted kelp being "the secret to beauty". Ester overhears this, which leads her and her friends to go out in search for it, only to discover that it turns their faces orange. When Ester tells her grandmother about this, she reveals that it is a beauty treatment for starfish and that she didn't want Ester or Spikey to know about it because she didn't want them to go near the bad-tempered lionfish that were guarding it at Rainbow Reef.