Although Donald Trump's first medical evaluation in office may have eased recent concerns about his mental state, it also sparked a mocking "girther" movement among those who question official findings that the president is 6-foot-3 and weighs 239 pounds. The #Girther hashtag quickly sprang up on Twitter -- it's a callback to the "birther" movement championed by Trump -- littered with joking demands that White House doctor Ronny Jackson release the president's "girth certificate." However, the writer/director of Marvel's Guardians of the Galaxy Vol. 2 went a step further, and offered money for a second opinion.

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In a series of tweets on Tuesday, James Gunn compared Trump's height and weight to Los Angels Angels first baseman Albert Pujols, who's listed at 6-foot-3 and 240 pounds, before getting down to business: a $100,000 donation to a charity of the president's choice if he'll step on the scale again.

I will give 100 thousand dollars to Trump's favorite charity if he will step on an accurate scale with an impartial medical professional, okayed by both of us. For real. #Girther #GirtherMovement— James Gunn (@JamesGunn) January 17, 2018

When someone accused Gunn of "fat-shaming," the filmmaker replied, "This has nothing to do with fat shaming. It has to do with a continuous pattern of fabricating facts by both Trump and his administration."

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Lest we think his questions pertain only to the president's weight, Gunn also posted a photo of the purportedly 6-foot-3 Trump alongside the 6-foot-1 Barack Obama.

A picture of a 6’3” man standing next to a 6’1” man and their wives. pic.twitter.com/VmnLjHfvMq— James Gunn (@JamesGunn) January 17, 2018

We'll update in the event the president takes Gunn up on his offer.