12/04/2012 10:45 am ET

Royal Rules Change Alert: If Kate And William Have A Girl, That Girl Is Queen

Almost as soon as Kate Middleton married Prince William and became the FUTURE QUEEN (consort) OF ENGLAND in 2011, the watch on her waistline began. For those eager for a royal pregnancy, the wait is over: Buckingham Palace confirmed today that Kate and William are expecting their first child.

As frantic tabloid editors brainstorm for the best headline and maternity-clothes designers plot to get their labels on that royal bump, Kate's pregnancy is a reminder that, no matter how modern this royal couple may be, it's impossible to wrench their role away from its ultimate purpose: to produce an heir and a spare to the British throne.

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