Mom takes the kids on a playdate with Tank Triceratops to the desert, where they meet a distant relative of Tank's, an early Ceratopsian named Penelope Protoceratops. The Conductor points out that Penelope lives in a part of the world that gets a lot of earthquakes, and sure enough, the kids experience their first quake with Penelope. Mom and the Conductor have prepared the kids with excellent advice about what to do in an earthquake, so everyone does fine. When the family rides the Dinosaur Train, they learn that a new car has been added - a Nursery Car, with dozens of eggs in little, padded nests, attended by their expectant moms and dads. The kids watch the eggs hatch, and try to guess which hatchling goes with which dinosaur parent.