Having argued successfully, with Hermione, that a week of work justified a day at the beach, the three Gryffindors had lain out a blanket beneath a giant colourful sunshade that Hermione had created from some curtains. Of course, the witch had brought a book, but Harry and Ron knew better than to think that anything but reading would relax her. They had planned to build a sandcastle after lunch to make up for the time they couldn't go swimming. Ron was wading through the crystal-clear water, looking for seashells and colourful rocks they could use as decoration later. A dot of yellow at the dunes drew his attention.