Happiness is...Awe and Wonder in my class

Today my class found an enormous egg in a huge nest in the wooded area at school!
Great excitement bordering on hysteria followed as my year 1 Daffodils and the other year 1 class became explorers and scientists as we used clues to work out what it was.
From the size, the tracks and the meat bones lying around they decided it was probably a carnivorous dinosaur. Then they identified it as a T Rex! A few of them even saw the mother T Rex running away from our loud screams and squeals! Their faces were priceless!
How long does it take for a T Rex egg to hatch? I'm getting worried!
Happy Tuesday