Every president except James Polk, Donald Trump ( President Donald Trump bucks this tradition, as the first POTUS in about 150 years to have no known pets at the White House) and Andrew Johnson had a pet for at least part of his time in office.
Many presidential pets have also become famous in their own right, like Warren G. Harding’s Laddie Boy and Franklin D. Roosevelt’s Fala.
Going all the way back to George Washington, many presidents have cared for dogs and horses, while others have brought slightly more exotic animals to the White House.