See the Duchess of Cambridge and Her Majesty ride the rails in honor of the London Underground's 150th anniversary
Updated: Wednesday Mar 20, 2013 | 07:00 PM EDT
By: Nancy Mattia
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Check out the sweetest snaps – including one bonus! – from the Prince of Cambridge's debut
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The expectant duchess gets pinned down with a "Baby on Board" button, given to pregnant riders so fellow passengers will know to offer up their seats. The Daily Mail reported Kate as telling the queen, "I will have to wear it at home!"
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