WASHINGTON (AP):

It's official: The Obamas have chosen a six-month-old Portuguese water dog to be the first pet.

In what was one of the White House's most tightly kept secrets, President Barack Obama's daughters, 10-year-old Malia and seven-year-old Sasha, have settled on a pup they named Bo, The Washington Post reported Saturday night. The black-and-white puppy is a gift from Senator Ted Kennedy, who owns several Portuguese water dogs himself. Bo is scheduled to make his big debut tomorrow afternoon.

Obama's daughters chose the name Bo because first lady Michelle Obama's father was nicknamed Diddley, the Post said. Bo continues the B legacy of his forerunners - George W. Bush's was Barney, a Scottish terrier, and Bill Clinton's Buddy, a Labrador retriever.