Mokuba Kaiba's "Blue-Eyes White Dragon" drawing
At a young age, Mokuba Kaiba hand drew a "Blue-Eyes White Dragon" card for his brother, Seto.
When Gozaburo ordered Hobson to confiscate all of Seto's toys, Mokuba hid Seto's Deck in a hollowed out book, including the drawing. He also left a note saying that their new family couldn't take everything away from them.
In the original Japanese anime, Mokuba wrote the card's name in hiragana, reflecting how at his then young age, he had not yet learned how to write in katakana or kanji (the script that the card's name is actually written in). In the dubbed anime, the text is removed.