Tsukasa's Grandfather

Marie's grandfather is a character of the day who appeared in Type Casting. He is the grandfather of Marie and also a Fisherman.

Ash and his friends first met him while trying to cross a river to reach Ecruteak City. His rowboat was their only available means of transportation after all of the river crossings had been destroyed by a typhoon a month prior. He agreed to take them across on one condition, that they catch him a rare Sudowoodo.

Team Rocket overheard the conversation and ended up capturing a Sudowoodo first. As they were about to present it to Marie's grandfather, James tried to water Sudowoodo with his Squirt Bottle, but this prompted Sudowoodo to run off. Having now seen a Sudowoodo, Marie's grandfather joined the chase. He eventually encountered Ash's group again, along with Marie, and revealed that he was only interested in catching the Sudowoodo to assist Marie's research efforts on the Imitation Pokémon.

Sudowoodo ended up fleeing again, but Marie declared that she and Pierre had witnessed enough of Sudowoodo's behavior to settle their debate on its typing. Marie's grandfather kept his promise and rowed Ash's group across the river.

(Source: Bulbapedia)