In "Rules of the Game," how does Waverly start playing chess?

In "Rules of the Game," Waverly begins playing chess when
she agrees to let her brothers use her Lifesaver candies as replacements for the missing
chess pieces in their chess set.  The children have received gifts from an annual
Christmas party, and the chess set that Waverly's brother receives has missing pieces. 
Their mother instructs them to discard the game, but Waverly's two brothers refuse to
give up the chess set, and they instead read the rules and learn how to play.   Waverly
wants to be included; however, her brothers do not want her to play.  She uses the
Lifesavers (her gift from the Christmas party) as a bribe to be let into the game. 
Afterwards, she learns the rules of the game and goes on to continue playing
chess.