First lady Jill Biden surprises with giant cutout Valentine’s Day hearts on White House lawn

The hearts contained messages including "unity" and "kindness."

First lady Jill Biden surprised the country with a Valentine's Day message Friday.

Biden unveiled at least half a dozen giant cutout hearts on the White House north lawn ahead of Valentine's Day this Sunday.

Each heart, which will remain on the lawn through the weekend, carried a message including "unity," "kindness," "strength" and "compassion."

“Overnight, the first lady’s surprise Valentine messages to the country were installed on the north lawn for the weekend, hearkening back to the days of sharing candy hearts between friends and family," a spokesperson for Biden said in a statement. "As you may know, the first lady is known for her sense of humor, love of surprises, and celebrating traditions, especially with her family."

"Valentine’s Day has always been one of her favorite holidays," the spokesperson said. "Sending messages of healing, unity, hope and compassion, this is her Valentine to the country.”

"We hope this lifted your spirits,” Jill Biden told reporters.

President Biden, who, like his wife, was holding a cup of coffee, told Americans to "stay strong" when asked for his message to people feeling discouraged during the coronavirus pandemic.

“There is hope. There’s hope. You just have to stay strong. A lot of people have gone through unbearable suffering. They’ve lost their families, lost their children, lost their husbands, wives, moms, dads, and it’s almost unbearable," he said. "The only thing I can say to them is that they’re still in your heart. Think about them in your heart. They really are. I can tell you from experience, they’re in your heart.”

Biden -- who is keeping her job as a college professor while first lady -- has been described by her grandchildren as a lover of pranks and "not your average grandmother."

"I would say she's not your average grandmother," Naomi Biden, one of Joe and Jill's grandchildren, said in a video last summer at the Democratic National Convention. "She's the grandmother that wakes you up at, what was it, 5 a.m. on Christmas Eve to go SoulCycle-ing."

"She's a prankster, she's very mischievous," Naomi added. "When she goes on a run, sometimes she'll find, like, a dead snake and she'll pick it up and put it in a bag, and she'll use it to scare someone."

Jill Biden was also known for her humor and her pranks during the eight years she served as second lady in the Obama administration.

On Valentine's Day in 2009, her first as second lady, she painted red hearts on the windows of his vice presidential office.

“She had taken her school kind of paint that kids put on poster boards [and] put a heart that said ‘Joe loves Jill,'" the president recalled Friday. "None of them said ‘Jill loves Joe.’”

The Bidens have been married for 43 years.

ABC News' Justin Gomez contributed to this report.