This is one of four possible quests that all share the same name. Unfortunately, Wowhead doesn't have them all grouped together under one title. Read what is asked by the quest giver, and chose the correct one.
For this one you have to purchase from the AH (or cook) a Tasty Hatchling's Treat. While you are at the Auction House, if you want the Snowclaw Cub pet, also purchase 3 Hormswog Hunk and 1 Honey snack.
Then go to 66.6,58.5 in Valdrakken to find the Despondent Duckling (it is near a group of Emerald Ducklings, and has a small cloud over it's head). Speak to it, and "administer the remedy".
The quest turn in marker on the map is wrong, so return to 72,8, 66.2 and turn in the quest to Thalendra. This will add a temporary (24 hours?, according to other posters) Title of "Honorary Dryad" to your list of titles. Don't equip the title yet.
If you want to collect the Snowclaw Cub pet, go to 67.6, 18.7 in the Azure Span. There are multiple posts about glitches causing the Title to be removed, so I dragon rode directly to the spot. There will be a cub pet there that will run away from you in fear. Open up your Character Info, and click on the Titles tab, scroll down to "Honorary Dryad", and click to select it. The title should appear at the top of your Character Info.
Now you can approach and click on the Snowclaw Cub.