Sept. 8, 1986: Nancy Reagan greets her dog as she and the president return to Washington. (Dayna Smith/The Washington Post)

President Johnson holds his pet dog ‘Yuki’ in the window of the car as the first family rides around the Texas ranch in Stonewall, Sept. 30, 1967. (AP Photo)

Many animal lovers know and savor that happy moment when a pet dog or cat runs up to greet them at the end of the day and the stresses of work and human interaction are melted away. The more stressful the day, the sweeter that evening reward.

Few jobs are probably more stressful than that of president of the United States, so it’s not surprising that a long line of commanders-in-chief have had de-stressers-in-chief living alongside them. Dogs seem to be first in line to fill this role, but cats, birds, horses, a raccoon and even a cow have found their places to bask in the White House sun.

President Lyndon Johnson and his family play with their pet beagles, Him and Her, in the White House flower garden, April 19, 1964.(AP Photo/Bill Allen)

President Johnson caused a huge controversy among animal lovers after he was photographed picking dogs named Him and Her up by their ears.

President Nixon walks along the beach with his Yorkshire terrier, Pasha, in front of his San Clemente home on the president’s 58th birthday, January 9, 1971. (AP)

President and Mrs. Ford, along with daughter Susan, admire their golden retriever Liberty and her litter of puppies at the White House, Sept. 17, 1975. (White House photo/AP)

President George H. W. Bush holds one of dog Millie’s six puppies for the press at the White House, March 29, 1989. (AP/Ron Edmonds)

President George H. W. Bush runs across the South Lawn of the White House with his dog Millie during a rain storm as they head for a helicopter waiting to take them to Camp David, June 23, 1989. (John McDonnell/The Washington Post)

Fala, President Franklin D. Roosevelt’s Scottish terrier, gathered up all his rubber toys at the White House in Washington and sat by wistfully as they were set aside for the Executive Mansion’s contribution to the scrap rubber collection, June 15, 1942. (AP/George R. Skadding)

President Herbert Hoover poses with his police dog, King Tut. (AP Photo/Hoover Library)

Mrs. Calvin Coolidge holds her pet raccoon, Rebecca. c. 1920-1930. (Library of Congress).

The Coolidges had a huge menagerie that included several raccoons, a dozen dogs, canaries, lion cubs, a wallaby, a donkey, a bobcat and a Pygmy hippopotamus, among others.

Pauline, pet cow of President Taft, stands on the lawn in front of what was then the State, War and Navy Building in Washington. (Library of Congress)

President George W. Bush and his dog Spot wait for his dog Barney on the South Lawn of the White HouseFebraury 5, 2004. Bush told Barney not to speak to the press. (Reuters/Mannie Garcia)

President George W. Bush’s pets India, left, and Miss Beazley face off on the South Lawn of the White House, October, 2006. (AP Photo/J. Scott Applewhite)

President Bill Clinton, Socks, nephew Tyler Clinton and dog Buddy play catch on the White House lawn, Oct. 3, 2000. (White House photo)

Socks peers over the podium in the White House briefing room, March 19, 1994. (AP Photo/Marcy Nighswander)

Bo (L) and Sunny, the Obama family’s new puppy, sit on the South Lawn of the White House. Photo distributed Aug. 19, 2013. (Pete Souza/White House/Reuters

The Washingtons had dogs, horses and a parrot. Thomas Jefferson had a mockingbird, bear cubs, dogs and a horse, and John Quincy Adams had an alligator. Both Presidents Taft and Harrison had a cow, and dogs, cats, goats and a turkey were only part of the entourage that lived with the Lincoln family. President Nixon had several dogs, but none as well remembered as Checkers, a dog he made famous in his 1952 Checkers speech. Ponies, hamsters, birds, dogs and other animals found room in the Kennedy White House, but probably the most notable of these was the offspring of a Soviet space dog given to JFK by Nikita Khrushchev.