Bonnie & Clyde, Napoleon & Josephine and Louis XV & Madame de Pompadour...they're all great love stories -on paper at least. But when you actually learn the whole story for all of these romances, they're a lot less sweet.
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If you're measuring by way of divorce, the myth of the seven year itch may not be a myth after all; according to the 2009 U.S. Census Bureau, the median duration of first marriages that end in divorce is 7.9 years.
The Fourth Doctor is particularly famous for his ridiculously long scarf, which resulted from a miscommunication between costume designer James Acheson and the knitter hired to produce it; Acheson never specified a length, and bought far too much yarn, so the knitter just kept going until it was all used up.