Rattle

The Rattle is a quest item from The Legend of Zelda: Skyward Sword. A colorful toy belonging to the infant child of Bertie and Luv, Bertie is seen using it to bring the baby into a calm state of mind. At one point, however, the Rattle is stolen by a bird, making it impossible for the baby to fall asleep, and by extent, Bertie as well. Bertie enlists the aid of Link in finding it, and surmises it may still be found hidden around Skyloft. Link eventually finds the Rattle stowed away in a bird's nest, and brings it back to the delighted Bertie and baby. Bertie's feelings of gratitude manifest themselves as five Gratitude Crystals.