Here are the top 3 theories for why Trump used back-door stairs to board Air Force One

As President Donald Trump arrived at Joint Base Andrews to depart for another weekend at his Mar-a-Lago resort in Florida, the White House press corps noticed two fascinating details. First Lady Melania Trump was not traveling with the president as was listed on the official schedule. And that Trump used the bellow-belly airstairs instead of the ceremonial staircase.

CBS News White House correspondent Mark Knoller reported that Trump walked from the Oval Office to Marine One alone.

"The official schedule said Mrs. Trump would be leaving with him, but she wasn't seen," he noted.

David Nakamura of The Washington Postnoticed the unusual use of airstairs.

"Looks like Trump used the non-ceremonial, below-belly stairs to board AF1 again. He did that a week or two ago. I almost never saw Obama do it. Wonder what that's about..."

On Twitter, speculation was largely grouped by speculation over the president's marriage, hair, and known fear of stairs.

Here are some of the top entries in each category:

Marriage Difficulties:

Combover Conspiracy:

Fear of Stairs: