They may seem like an unlikely pair, but Michelle Obama and former President George W. Bush have a warm, genuine friendship with one another.

SAUL LOEB via Getty Images George W. Bush smiles as he speaks with Michelle Obama during an event marking the 50th Anniversary of the Selma to Montgomery civil rights marches at the Edmund Pettus Bridge in Selma, Alabama, March 7, 2015.

“That surprised everybody,” Bush told Ellen DeGeneres on a recent episode of “Ellen.” “That’s what so weird about society today. People on opposite sides of the political spectrum could actually like each other.”

Mike Blake / Reuters Bush and his wife, Laura, wait to pay their respects with Obama and California Governor, Jerry Brown, during the funeral for former first lady Nancy Reagan in March 2016.

Yet, the reason why the two get along so well is pretty simple: Bush makes Obama laugh.

“She kind of likes my sense of humor. Anybody who likes my sense of humor, I immediately like,” Bush told People while promoting his new book, “Portraits of Courage,” which features his paintings of military veterans.

BRENDAN SMIALOWSKI via Getty Images Obama reaches to embrace Bush and wife, Laura, during a portrait unveiling ceremony.

Bush explained to the magazine that he and former first lady were often seated next to each other at events such as an interfaith memorial service for Texas police officers in July and Nancy Reagan’s memorial service in March 2016.

Tom Pennington via Getty Images President Barack Obama and first lady Michelle Obama embrace Bush during an interfaith memorial service, honoring five slain police officer on July 12, 2016 in Dallas, Texas.

“I can’t remember where else I’ve sat next to her, but I probably have a few wise cracks and she seemed to like it okay,” he told People. “I needle her a little bit and around her, I’m fairly lighthearted. [The Obamas] are around serious people all the time and we just took to each other.”

Joshua Roberts / Reuters Obama hugs Bush as she arrives for the dedication of the Smithsonian’s National Museum of African American History and Culture in Washington, U.S. in September 2016.

The two also sat next to each other at the opening dedication ceremony of the Smithsonian’s National Museum of African American History and Culture in September 2016. The photos of the two of at this particular event went viral.

ZACH GIBSON via Getty Images The viral photo of Bush and Obama at the opening ceremony for the Smithsonian National Museum of African American History and Culture.

When asked about the pals’ vibe in these photos, Bush told People:

“When I saw her, it was a genuine expression of affection.”

Aw shucks, you guys!