Ok, I cannot remember its name at all. I'll spell out a scene near the intro, though.

I remember three kids awakening an absolutely huge white dragon..I remember one being kinda chubby. I remember him immediately speaking in a.."proper" medieval dialect, in which the dragon kinda responded bluntly. I remember them asking for a "dragon jewel" or "dragon gem", which the dragon started to respond that it's merely his poo, crystalized..I know they had to travel to get it appraised, but not much more.

Which game is this?