Even after a multiyear friendship, the couple left this famous duo off of their invite list.

Figuring out who to invite to your big day is arguably the most challenging part of the wedding-planning process. There are many potential factors to consider, including someone’s relationship to you, her role in your relationship, and her ties to other guests. And, unfortunately, whether due to cost or restrictions on space, certain people have to be left off of the list—something that happens to even the most famous people in the world. That’s exactly the situation former President Barack Obama and First Lady Michelle Obama found themselves in for Prince Harry and Meghan Markle’s May 19, 2018, nuptials.

Harry’s relationship with the Obamas dates back to 2015, when he met with the former president for an informal chat in the Oval Office to discuss his work with the Invictus Games. During his visit to the nation’s capital, Harry also spent time with the former first lady (and the current first lady!) while delivering remarks to veterans in Virginia. Harry’s relationship with the famous couple continued through the years: He hosted the former president at Kensington Palace in May 2017, and joined Michelle to speak with high school students on the South Side of Chicago later that same year.

However, a source also claims that the couple played a role in the prince connecting with his now-wife, Meghan Markle, who he met in 2016. “Michelle had a hand in introducing Harry to Meghan,” a source reported to the Daily Mirror. Yet that introduction didn’t seem to secure the Obamas an invitation to the 2018 royal wedding.

Since Harry is not likely to become king, his royal wedding was not considered an official state occasion. As a result, he and Meghan weren’t under any obligation to invite any political leaders to their nuptials. Reports indicate that the couple didn’t want to invite the U.S. president at the time, and in an attempt to avoid any type of diplomatic chaos, decided to also leave the Obamas off of their invite list. Yet the snub didn’t appear to sit well with Harry. “In his mind there wouldn’t be a wedding without [Michelle] and that is reason enough to invite them,” a source reported to the Daily Mirror. “He was not happy such a legitimate reason was ignored.”

Even though the Obamas weren’t in attendance at the couple’s Windsor Castle nuptials, other famous figures were present at the 600-person affair. Serena Williams, Priyanka Chopra, Patrick J. Adams, George Clooney, Oprah Winfrey, Idris Elba, Elton John, and the Beckhams all attended the couple’s royal wedding. Some A-list stars took on even larger roles at the couple’s reception: Elba reportedly served as the DJ at the celebration at Frogmore House (playing hits such as “Still D.R.E.” by Dr. Dre and “I Wanna Dance With Somebody” by Whitney Houston), while Clooney stepped in as a bartender. Williams also joined in on the fun, showing off her athleticism while playing a game of beer pong.