We Went to Find a T. Rex

We went to find a T. rex . . . and it was NOWHERE to be found.
It wasn’t hiding in the ferns. Or swimming in the river. And it DEFINITELY wasn’t flying high in the sky.
Everywhere we looked, we found other dinosaurs instead. There was a towering triceratops with its pointy beak and fancy grills. A super huge stegosaurus that was having an afternoon snooze. And a scary spinosaurus that we had to swim past VERY carefully as it ate a pile of fish for lunch. But absolutely NO sign of a T. rex.
Where could such a HUGE great dinosaur be hiding?