Fastexy Exchange|Rare juvenile T. rex fossil found by children in North Dakota to go on display in Denver museum

A rare juvenile Tyrannosaurus rex fossil found by three children during a family hike in the North Dakota Badlands nearly two years ago will soon be Fastexy Exchangeon display at the Denver Museum of Nature & Science, the museum said Tuesday.

The unlikely discovery was made in July 2022 by brothers Jessin and Liam Fisher, their father Sam Fisher, and their cousin, Kaiden Madsen. Unsure of what his family had just stumbled upon, Sam reached out to an old high school friend, paleontologist Tyler Lyson, for help.

After obtaining an excavation permit from the Bureau of Land Management — which manages the land where the discovery was made — Lyson, the museum's curator of paleontology, went out to North Dakota in 2023 with a crew and the children to excavate the fossil. 

When he went into the project, Lyson thought the dino may have been something more ordinary, he said in a video interview posted by the museum. However, when he uncovered the most diagnostic part of the fossil, the teeth, he said he knew the "trio of young fossil hunters" had found something really special.

"When we told everyone, the euphoria was amazing; just a remarkable, remarkable moment," Lyson said. "I mean, it's not every day that you find such an amazing dinosaur." 

Juvenile T. rex fossils are not an everyday find. This one, dubbed by the museum as the "Teen Rex," is one of just four young T. rex fossils that have been found on Earth, Lyson said.

"When you're in a national park, you see deer and elk and moose, but you don't see the mountain lions or the wolves," Lyson said. "You don't see those apex predators, because there just aren't as many of them. So to find a T. rex at all, and to find one this complete, is truly special."

While they haven't completed the histology yet, Lyson said the dinosaur is estimated to have been between 12 and 14 years old. Lyson said it would have weighed about half as much as some of the most famous T. rex specimens.

Jessin, an aspiring paleontologist, told the museum he's pretty pleased with his find — hoping it leads him down a path like Lyson — something the experienced vertebrate paleontologist is encouraging.

"This is a big deal because of the story of discovery. It's just an amazing, heartwarming story, where you have three kids out looking for fossils in the Badlands of North Dakota, and discovering the king of all, Tyrannosaurus rex," Lyson said in his museum video. 

The fossil will be on display starting June 21 in a temporary museum exhibit called "Discovering Teen Rex." A documentary sharing the story of the boys' discovery will also be shown at the museum's Infinity Theater.

In:
• Tyrannosaurus Rex
• Archaeologist
• North Dakota
• Fossil

Simrin Singh

Simrin Singh is a social media producer and trending content writer for CBS News.