Captain Morgane and the Golden Turtle

Missable! I recommend doing this as soon as possible, even the first time you're at the Dark Reefs, because when the wish is fullfilled during the course of the game without you having made Morgane actually making the wish, the trophy will be lost. At the Dark Reefs on Hollow Island, there is a puddle of water on the lower right side of the screen. Use a doubloon on it and Morgane will throw it in the water, making a wish. You can choose one of three options and all of them will be fullfilled eventually, but since the one about her father finding peace is the earliest of the three to come true, you might want to pick that one.