paragraph: Littlefoot 's grandfather one night tells the children a story about `` The Lone Dinosaur '' , a legendary longneck who once protected the Great Valley from the most ferocious sharptooth ever to live . A fight ensued , which led to the Sharptooth 's death . However , the sharptooth left `` The Lone Dinosaur '' with a scar slashed across his right eye . Soon after the battle , a huge monolith that resembled a proud sauropod , having life-sized Sharptooth teeth arranged around his neck , came out of the ground during an earthquake . The dinosaurs called it `` Saurus Rock '' . The legend also states that if anyone damages the monolith , bad luck would descend upon the valley . A few days later when the kids are playing , Littlefoot accidentally falls off a cliff . Just before he hits the ground , a gruff Diplodocus rescues him . This longneck introduces himself only as `` Doc '' and gives no knowledge of his history . Littlefoot is intrigued by this newcomer , who is scarred across one eye and displays prior knowledge of the Great Valley 's topography . For the preceding reasons , Littlefoot assumes that Doc is the Lone Dinosaur . He tells his friends this , narrating an apparently extemporaneous legend to support his assumption . Inspired , Cera 's infant nieces , the twins Dinah and Dana , go to Saurus Rock without anyone noticing . Later when the friends are playing , they notice that Dinah and Dana are missing . Recalling their talk of the day before , they go to Saurus Rock to find them . 
question: Who went to Saurus Rock to find Dinah and Dana?
answer: Littlefoot and his Grandpa