Submerge the big 4.5 inch toy dinosaur egg in water for 48-72 hours and watch the baby dinosaur figurine hatch, then slowly grow to nearly 12 inches in size! Figures can be dried out and re-grown. Your little paleontologist will be delighted when his 4.5 inch dinosaur hatches into some mysterious dinosaur in 48 72 hours. These are must haves for Easter egg hunts!