Bo Obama, the most famous dog in America, has a little sister. The first lady tweeted a picture of the new arrival.

Sunny, a Portuguese water dog, was born last summer in Michigan and made her debut at 1600 Pennsylvania Ave. on Monday. Unlike all the hoopla leading up to the birth of the royal baby last month, the new addition to the Obama family came mostly as a surprise to the general public. Although presidential pooch aficionados could have read the tea leaves back in October, when Michelle Obama told reporters that she hosted a “doggie play date” because “Bo doesn't have enough dog interaction.”

By the looks of the video below, it seems Bo and his little sister are already enjoying each other's company.

According to the official White House blog, the first family will be making a contribution in Sunny's honor to the Washington Humane Society.

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