“Meanwhile: 39 shootings in Chicago this weekend, 9 deaths. No national media outrage. Why is that?” Posobiec tweeted.
The tweet was one of several from the president on Monday that appeared to highlight his frustration over the media's coverage of him.
Posobiec, a staunch Trump supporter, livestreamed his reaction to the retweet news on Twitter and later thanked the president in a separate Twitter post.
Just days after Trump was elected president, Posobiec livestreamed a visit to the pizza shop at the center of the theory to investigate, but was removed by police for videotaping a child’s birthday party there.
A man fired multiple shots into that same pizza shop about a month later, claiming he had driven from North Carolina to “investigate” the false claims of an alleged child sex ring at the shop. Edgar Maddison Welch was sentenced in June to four years in prison after pleading guilty to firearm and assault offenses in March.
Posobiec has also pushed unsubstantiated claims that the Democratic National Committee was responsible for the death of former staffer Seth Rich. A story published by Fox News in May that fueled the rumors surrounding Rich's death was later retracted and has now become the subject of a lawsuit.
The retweet from Trump came just hours after the president made a second statement about the rally in Charlottesville, Virginia, on Saturday after he was criticized over the vagueness of his initial response.