Did Cole Tomas Allen's brother or family give the police a warning 48 hours in advance of his shooting at the White House Correspondents' Dinner? No, that's not true: Court documents filed in the case against Allen state that members of his family found out minutes before the attack. According to the documents, an email was sent to members of the defendant's family, friends, and a former employer.
The claim appeared in a post and image (archived here) by the @JamesTate121 account on X on April 29, 2026. It read:
Get rid of this whole corrupt administration! This is not the America that you were raised in this modern day Russia North Korea!
This is what the image in the post looked like on X at the time of writing:

(Image source: post by @JamesTate121 on X.)
The image is a screenshot of a post by the jeffpetersla account (archived here) that first appeared on Threads after the shooting on April 25, 2026, but was later deleted. It said:
Based on the information we have now, the attack may not have been staged, but they knew he was coming and let him through to create chaos and fear in order to further their ballroom bunker agenda.
His brother notified police 48 hours in advance, he was on a watch list, people at the venue were warned, Leavitt couldn't resist teasing it just prior, Trump showed no surprise, and his entire dossier was ready for the smug, smiling press conference.
They let him through on purpose.
Although Peters deleted the original post, saying he didn't "want to spread false information," he continued updating his account over time. In a post (archived here) on Threads on April 27, 2026, at 4:23 p.m., he said:
That info has changed in the last 18 hours. From 48 hours before to 10 min before, now 2 hours after.
Soon the brother will notify police tomorrow.
This is what the post looked like on Threads at the time of writing:

(Image source: post by jeffpetersla on Threads.)
In a post (archived here) on Threads on April 27, 2026, at 10:25 p.m., he said:
[Reply to unavailable post]
This post is based on the info reported 24 hours ago.
It has chamged [changed]. First it was reported as 48 hours before, ( I posted my post) then changed to 10 min before, now they say 2 hours after.
Soon the brother will notify police tomorrow.
Regardless, he was on a watchlist and allowed to cross the country and check in to the hotel that the entire administration was coming to.
This is what the post looked like on Threads at the time of writing:

(Image source: post by jeffpetersla on Threads.)
In a post (archived here) on Threads on April 29, 2026, at 12:10 a.m., he said:
Sorry, I don't know where you got this screenshot, but I have archived the original, since the data has changed since it was first posted and I don't want to spread false information.
The SS [Secret Service] knew 10 minutes before the attempted entry and Allen was not on a watch list.
Unfortunately, I can't control where this has been posted and reposted.
This is what the post looked like on Threads at the time of writing:

(Image source: post by jeffpetersla on Threads.)
Department of Justice
Court documents (archived here) filed on April 29, 2026, by the Justice Department in the case against Allen, confirm that his family did not warn police 48 hours in advance of the incident. Page six of the filing states:
At some point before the attack, the defendant wrote emails explaining the actions he was about to take and scheduled those emails to be sent to specific people at approximately 8:30 p.m.
on April 25 -- just minutes before the defendant, laden with weapons, sprinted through the screening checkpoint toward the Dinner. The email recipients included members of the defendant's family, friends, and a former employer.
The attack (archived here) at the dinner took place at approximately 8:36 p.m. ET on April 25, 2026.