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Michelle Obama: Bo Is My Son

UPDATED 03/21/2012 at 05:30 PM EDT • Originally published 03/20/2012 at 01:30 PM EDT

Michelle Obama made a surprising confession Monday night about her dog, Bo.

"He is my son," the First Lady told David Letterman. "I have two girls – and a boy."

Obama has always said she considers herself the Mom-in-Chief, and in true mom form, she had nothing but praise for her furry kid. "Bo is wonderful," she said. "He is the smartest dog on the planet." When Letterman expressed doubts about Portuguese water dogs and their behavior, Obama assured him that Bo has nothing but positive qualities.

"He's a very sweet dog. I'm not being biased. He's very well-mannered, he's very even-tempered," she said. "He has a very busy schedule, appearances. I'm thinking about getting him an agent."

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