From Bulbapedia, the community-driven Pokémon encyclopedia.
Walda Pepper (Japanese: アヤノ Ayano) is a young girl in Rustboro City who is very sick. Her father bought her multiple Poké Dolls—such as Pikachu and the Hoenn starters—to cheer her up, but it has not worked. If the player is able to say something to make her laugh, her father will reward them with a new wallpaper for their Pokémon Storage System.
Words that will make Walda laugh usually consist of random characters and depend on Trainer's ID number.
|| From 文 aya, design.
||From bercer, to rock.
||From Tapete, wallpaper.
||From papel, paper.
Pokémon Emerald Secret Word Generator on filb.de