Orielle's Injured Loftwing
Orielle's Injured Loftwing is a side-quest in Skyward Sword.
The Concerned Brother
After speaking with Batreaux about Gratitude Crystals, you'll find Parrow wandering in circles in the Plaza of Skyloft (far south) with a thought bubble above his head. You can chat with him to hear his worries over his missing sister, Orielle. She went flying recently and has been gone much longer than she normally would be. He says the following:
"She said she was curious about that colorful island that appeared recently, so I suspect she's somewhere in the southwestern sky."
You wouldn't mind investigating the issue, right?
As you travel to the southwest, you'll see Fun Fun Island in the distance. A little ways before it is a small, green island where you'll easily spot Orielle and her Loftwing. Dive off your own bird and have a chat with her. She explains that her bird got injured and she had to make a crash landing here on this small platform. She doesn't want to leave her bird and she needs bird medicine. In fact, her brother probably has some.
At this point, you can head back to the Plaza in Skyloft and speak with Parrow, who will give you a Bottle of Mushroom Spores. Alternatively, you can also get Mushroom Spores in Faron Woods or Deep Woods by slashing mushrooms and swiping the Bottle to catch the spores.
NOTE: This event grants you one of the five Bottles in the game, but if you got the spores yourself, you can return to Parrow later and he'll reward you with a Bottle in thanks instead.
Return to Orielle and speak with her. Once the dialog option appears, hand her the Spores and she'll sprinkle them on her bird's wing. Good as new! She's so thankful that you'll receive five Gratitude Crystals! Now doesn't helping people feel good?
We're not done yet! Return to Parrow in Skyloft and he'll be extremely grateful as well, giving you another five Gratitude Crystals! This is the only quest that yields 10 total Gratitude Crystals from people.