• English / United States: Grandma Wilma
• Japanese / Japan: タツばあさん
• Japanese (Romanized) / Japan: Tatsu Baasan
• Japanese (Trans) / Japan: Grandma Tatsu

Grandma Wilma is an old woman that lives in a forest near Daybreak Town. She is based off the Move Tutor who teaches the powerful Dragon-type move Draco Meteor to trainers' Dragon-type Pokémon in the Gen IV Pokémon games. [The Move Tutor lives in Route 210 in Diamond, Pearl and Platinum, and in Blackthorn City in HeartGold and SoulSilver and can only teach the move to Pokémon that have a maxed out friendship meter.]

Ash Ketchum and his friends met Grandma Wilma when they got lost in a forest while heading to Daybreak Town for Dawn's next Pokémon Contest. They noticed Grandma Wilma's Altaria's Draco Meteor attack in the air and rushed towards the site they saw it come from. When they reached it, they saw Grandma Wilma training with Altaria in perfecting Draco Meteor. After successfully avoiding getting hit by the falling meteors that came from Altaria's attack, Grandma Wilma introduced herself to Ash Ketchum, Dawn and Brock, and explained to them that the move they had just witnessed was Draco Meteor, a powerful Dragon-type move she can teach to trainers' Dragon-type Pokémon. She also informed them that the area near her house is out of bounds to people and Pokémon, because nobody knows where a Draco Meteor attack, that comes from Pokémon who haven't mastered the Dragon-type move yet, will land.

During their conversation, Ash Ketchum and his friends asked Grandma Wilma to let them watch her train with Altaria so they could see how she teaches Draco Meteor to Pokémon, and she agreed to do so. While they were training, though, Team Rocket appeared and stole Altaria. Ash Ketchum and Dawn, along with Brock who was carrying Grandma Wilma on his back, went after them, and were at last able to catch up to them. After defeating Team Rocket in a battle, with the help of Ash's Gible (who was still a wild Gible at the time), Ash Ketchum and his friends managed to reunite Grandma Wilma with the Altaria she was looking after. Grandma Wilma then said farewell to Ash Ketchum and co. and also gave them advice on which route to follow in order to reach Daybreak Town.

Altaria is shown to have developed a really strong bond with Grandma Wilma, even though it's a Pokémon that doesn't belong to her. This is more evident when Grandma Wilma got really upset after Team Rocket stole Altaria from her.

Grandma Wilma is also shown to get on really well with Ash's Gible when it was still a wild Pokémon living in the forest near her house. She was the one who introduced it to Ash Ketchum and his friends, and was later able to calm it down by petting it, so that it would stop biting on Ash Ketchum's and Dawn's Piplup's heads. She told Ash Ketchum and co. that it had shown up before them because it must have taken an interest in them.