Tiny mark on Melania Trump's birthday card to Donald Trump sparks wild theories

Of all of the strange theories about Donald and Melania Trump, this one is possibly the most bizarre.

On Wednesday it was the 71st birthday of President Donald Trump and his wife wished him well via Twitter.

But a subtle detail on the image of a birthday card she tweeted to her husband has left many online scratching their heads -- a small orange dot.

Since she published the image on Wednesday evening, more than 40,000 users have "liked" the first lady's post -- and many have speculated on about whatever could have caused the glaring stain.

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Here are a few ideas, according to the people of Twitter.

Some argued the small dot came from the president's finger print, given his previous issues with the size of his hands.

Others linked the mark to covfefe -- the president's Twitter typo from late May that's taken on a whole new meaning.

And then came the spray tan jokes.

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