Don't mess with this little guy—or his big sister.

Bristol Palin leapt to her brother's defense Tuesday after celebrating World Down Syndrome Day on her social media. The mother of two shared a photo of her youngest sibling, Trig Palin, who was smiling into the camera while wearing a knit hat that read "Make America Great Again!," Republican presidential candidate Donald Trump's famous campaign slogan.

"World Down Syndrome Day!!" she captioned a photo of her 7-year-old brother on Instagram. "I don't know how our family got so lucky to have this handsome boy light of our lives without a doubt #theluckyfew #TrigPaxson #T21 #mybrotherhasmorechromosomesthanyou"

Fans of the former Dancing With the Stars competitor gushed over Trig's sweet smile and offered words of encouragement. However, one user didn't take too kindly to his beanie hat.

"Yep that's Trumps target demographic," the user, who is a nursing student, remarked.