What are the motifs in The Westing Game by Ellen Raskin?

In the Westing Game, the will becomes a recurring motif in the story. It ties everyone into the solving of the mystery, binds them together for a purpose, and eventually succeeds in choosing an heir. The will, itself, is a sort of statement of regret; to all of those people that Sam Westing wronged, abused, or neglected. The will is symbolistic of the need to right old wrongs and to bury the past.

The game is the other motif. The game challenges everyone, has a set of rules, and everyone knows what the goal is. And, interestingly enough, each character has a side-game that they are playing on their own, with one of the others.