Both dogs were spotted frolicking on the White House lawn on Monday and barking could be heard after Biden signed an executive order in the Oval Office in the afternoon.
The first dogs officially arrived at the White House on Sunday. According to first lady Jill Biden's office, the Biden family wanted to get settled in the White House before moving Champ and Major from Delaware to Washington.
"Champ is enjoying his new dog bed by the fireplace, and Major loved running around on the South Lawn," the first lady's office said in a statement.
The Bidens told CBS in November the family expects to soon welcome a first feline.
White House press secretary Jen Psaki predicted in a video posted Sunday that Biden's first cat would "dominate the internet" when the cat is publicly revealed for the first time.
"I am also wondering about the cat, because the cat is going to dominate the internet whenever the cat is announced and wherever that cat is found," Psaki said, responding to someone who had tweeted asking for details of the first cat.
Just a few days ahead of Biden's Inauguration Day, the Delaware Humane Association -- where Major was adopted from -- was hosting an "indoguration" ceremony via Zoom. Touted as the world's largest virtual party for dogs, it was actually a fundraiser for the association.
"Let's celebrate the first-ever shelter pup to become First Dog and raise $$$ to help more shelter animals like Major live the American Dream," the Facebook post announcing the celebration said.
Champ, a name given by his grandchildren, but also the nickname Biden's father gave him when he was a child, lived at the vice presidential residence at the U.S. Naval Observatory. Months into his first term as the second dog, the family had to replace the off-white carpet at the residence with hardwood floors because of "the occasional puppy accident," a Biden spokeswoman told The Washington Post at the time. She added that he'd "generally been a good dog."
Both Champ and Major are frequently featured on the Biden family's social media pages and made several appearances leading up to the election in an appeal to pet lovers.
"No ruff days on the trail when I have some Major motivation," Biden wrote alongside a video of Major licking his face.
The Biden campaign even launched "Dog Lovers for Joe" with the slogan "Choose your human wisely" and ran on the promise that dogs would return to the people's house.
"Red state or Blue state, we all can agree on the power of dogs," the website said. "It's time we had a dog-lover back in the White House."
Former President Donald Trump was the first president in more than a century not to have a pet of some kind at the White House. Trump reportedly doesn't like dogs and in February 2019 said he doesn't "have any time" to have a pet and that getting one "feels a little phony."