Dinosaurs, like all modern birds and most reptiles, laid eggs. In recent years, many fossilized eggs and nests have been discovered, although we arenâ€™t always sure what kind of dinosaur they belong to. History: Although we have never been able to identify a T. rex nest full of eggs, we do know that many other dinosaurs made nests, so T. rex almost certainly made them as well. Typically, the parent dinosaur would dig a shallow pit, lay the eggs in it. Each species of dinosaur appear to have laid the eggs in a characteristic pattern (e.g., in a ring, or standing on end) and then cover them with some soil or vegetation. Scientific Name: Tyrannosaurus rex Characteristics: Unlike the adults, the body of a baby T. rex was slim and its hind legs were long, suggesting that it was a very fast runner. As this T-Rex Baby toy demonstrates, although its head was relatively large, its jaws and teeth were smaller and more lightly built than the adult.