President Barack Obama arrives with his dog Bo to read Chicka Chicka Boom Boom during activities at the annual Easter Egg Roll on the South Lawn of the White House in Washington, Monday, April 1, 2013. (AP Photo/Susan Walsh)

One aspect of White House life that sets President Donald Trump apart from several of his predecessors is that the sitting commander-in-chief does not have a pet.
 
According to the Presidential Pet Museum, Trump is the first president since Andrew Johnson, who served from April 15, 1865 to March 4, 1869, to not own a pet of any kind.
 
The Presidential Pet Museum does say Johnson was known to leave flour on the floor for a family of mice, but that doesn’t really count as pets.
 
Trump’s predecessor, Barack Obama, had two Portuguese water dogs, Bo and Sunny. Before him, George W. Bush had several animals, including Miss Beazley, a Scottish terrier, Spot, an English springer spaniel, Barney, a Scottish terrier, India, a cat and Ofelia, a longhorn cow at his ranch in Crawford, Texas.

FILE – In this Feb. 3, 2003 file photo, President Bush slows his pace to wait for his dog Barney as he walks to the Oval Office at the White House in Washington, Monday, Feb. 3, 2003. Barney, former White House Scottish Terrier and star of holiday videos shot during President George W. Bush’s administration, has died after suffering from cancer, the former president announced in a statement Friday, Feb. 1, 2013. He was 12. (AP Photo/J. Scott Applewhite, File)

 
Dogs remain the most popular presidential pet, but cats have also been popular among commanders-in-chief.
 
In the post-World War II era, John F. Kennedy appeared to have been the biggest animal lover. According to the museum, Kennedy had 22 pets, including several dogs, birds, a rabbit and a pony. One of the dogs, Pushinka, was a gift from former Soviet leader Nikita Khrushchev.

First lady Hillary Rodham Clinton looks on as President Clinton holds first Socks who is petted by a Washington area elementary school student in the State Dining Room of the White House in Washington on Friday, Dec. 17, 1993. The President and Mrs. Clinton hosted the students with the President reading ?The Night Before Christmas.? (AP Photo/Joe Marquette)

 
Some of the more exotic presidential pets, according to the museum, include Calvin Coolidge’s pet goose, Enoch, Theodore Roosevelt’s flying squirrel and snake and Benjamin Harrison’s opossums, just to name a few.
 
The New York Post reported that Trump was about to get a pet, a goldendoodle, which is a cross between a golden retriever and a poodle, from friend Lois Pope, a Florida philanthropist.
 
“Every president has had a first dog, and he did not have a dog,” Pope, 83, told the Post. “I wanted to find a dog with a great disposition, and I didn’t want a small dog. He’s a guy who is 6-foot-2. He doesn’t want a small dog.”

FILE– Richard Nixon is seen with his dog “Checkers,” at his home in Spring Valley neighborhood of Washington, DC., in this July 2, 1959 file photo. Not even a president should be separated from his faithful dog, especially if the canine helped save his political career. The body of Richard Nixon’s cocker spaniel, Checkers, may be exhumed from a New York cemetery and reburied near the former president and his wife Pat in California. (AP Photo/ FILE)

 
In the end, however, Pope decided to keep “Patton” despite the animal having been chosen for Trump because of its temperament, lack of shedding and burnt orange color.
 
“Donald said, ‘But, Lois, I can’t take the dog,’” Pope told the Post. “He said, ‘Look at what I do. I’m here, I’m in New York, I’m in Washington. What am I going to do with the dog?’ And I said, ‘Well, you can’t have him!’”
 
It is not clear why Trump does not have a pet. Some say his alleged germophobia is the reason, but no one really knows.

Pushinka, a gift to Presdient John F. Kennedy from Soviet Premier Nikita Khrushchev, stands her ground on the White House lawn, Aug. 14, 1963, while the rest of the family’s dogs vacation with the first family at Cape Cod. Pushinka was the offspring of Soviet space dog Stelka. (AP Photo/William J. Smith)

 
The pet museum wrote in a blog post that they think Trump will eventually get a pet.
 
“We at the Presidential Pet Museum suspect this will quickly change when President-elect Trump gets to the White House. Why? Because every single presidency since Theodore Roosevelt’s (1901–09) has had a dog at the White House. So for that reason, we’re certain we’ll see a wagging tail soon after the inauguration.”
 
Given the stress of the job, it might be a good idea for Trump to get a pet, as they are reportedly good for people’s health.
 
According to The Huffington Post, pets can improve heart health, help a person remain active and maintain a healthy weight, and reduce stress, among benefits.