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Happy Birthday, Bo! You're 4 Years Old!Wag those tails! The First Dog adds another candle to the cake on Oct. 9
Credit: Art & Martha Stern/AP
Updated: Sunday Oct 09, 2011 | 06:00 AM EDT
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It's hard to believe that Bo once was this tiny, but he was. With the help of the late Sen. Ted Kennedy and his wife, the puppy went from a breeder to a Virginia dog trainer, and finally, to the White House.
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