Clifford Gathercole 
Hide and Seek Grandad At the Beach [EPUB ebook] 

Jack and Amelia Barker were brother and sister who lived at home with their parents. Like many children, they laughed and played together, watched TV, and sometimes they even squabbled! They loved mealtimes around the table to enjoy yummy food and share what had happened in their day. Like many children, they also had a grandad. He was a cheeky grandad who was always telling jokes and making them laugh. But most of all, he always seemed to know when they had a day out and find the best place to hide from them and surprise them. This Saturday they were heading to the beach for a day in the sand and sea. I wonder if Grandad would be there and, if so, where they might find him.