The simian crease is one of the listed signs in Down Syndrome which would imply there's some genetic factor at play. My eldest daughter has a simian crease on one hand and the other hand is 'normal'.
Sovereign definition, a monarch; a king, queen, or other supreme ruler. See more.
Crown(noun) the Crown (or the reigning monarch) as the symbol of the power and authority of a monarchy. the colonies revolted against the Crown. crown(noun) the part of a tooth above the gum that is covered with enamel. crown(noun) a wreath or garland worn on the head to signify victory.