They had two requirements: First, 10-year-old Malia is allergic, so they needed the dog to be hypoallergenic. When the Obama girls met Bo a few weeks ago, Malia had no allergic reaction, according to ABC News' Jake Tapper.
And second, they wanted a shelter dog.
"This has been tougher than finding a commerce secretary," Obama told George Stephanopoulos in January.
After months of speculation, Sen. Ted Kennedy, D-Mass., who himself owns two Portuguese water dogs, "gifted" the Obamas with the 6-month-old Bo on Easter weekend. The senator sometimes takes his dogs, Sonny and Splash, along with him to work on Capitol Hill and has written a children's book about their adventures.
Bo was bred by the same breeder as Kennedy's dogs. And because they did not get a dog from a shelter, the Obamas have pledged to make a donation to the D.C. Humane Society.
Malia Obama and are her 7-year-old sister, Sasha, named the black-and-white puppy Bo because their cousins have a cat named Bo and first lady Michelle Obama's father was nicknamed "Diddley," after the guitarist and songwriter Bo Diddley, according to The Washington Post. There's also speculation that the dog may have been named after the president himself, given that "Bo" spells out the president's initials.
In a congratulatory letter to the Obamas, the Humane Society of the United States noted: "The unconditional love of a dog can be particularly welcome for a first family as they face life in the public eye and the stresses of the presidential job. Just about every president has had a pet of some kind, and since the Civil War especially, pets have been a fixture at the White House. Most presidents have been dog owners, and more than 50 dogs have occupied its hallowed hallways."
But even though the mystery of the dog is finally solved, don't expect to see it with the Obamas right away. Bo the first dog will not make an appearance at the annual White House Easter Egg Roll happening Monday.
"I think it's important for them to get to know each other," White House social secretary Desiree Rogers said on "Good Morning America." "It's part of the all-American family. ... Every child wants a puppy, I think they've got theirs. ... More to come."