The seven dragon tribes are ruled by dragon queens. Only their daughters, sisters, nieces, and granddaughters can serve as potential successors to the throne, with the exceptions of RainWings, MudWings, and occasionally SandWings. Since the MudWings have a leader in the group of siblings, called the "BigWings", all sisters are loyal to her and will not challenge her for queenship because they are too loyal to their siblings. Another way is for the queen to die of some other cause such as sickness (See Queen Glacier), murder (See Queen Vigilance), or unfortunate accident (see Queen Oasis).