spokesmoppet
A child, usually a teenager, that is granted moral authority by the mainstream media because s/he was the victim of a dastardly crime or event, and is used by the media to pontificate to the general public in support of the media's stance on a particular social or political issue related to the aforementioned crime or event. The term was first coined by "Ace" at the conservative Ace of Spades blog in reference to David Hogg and others that participated in the "March For Our Lives" rally on March 24, 2018.
Children's March Spokesmoppet Tells CNN's Media Analyst Brian "Tater" Stetler That "Journalism is Activism" .