If you venture inside Cliffspring Falls in Darkshore, you’ll find Apothecary Furrows who is friendly to Horde. To Alliance, he’s an NPC which may be killed for a quest item. Horde players can simply buy the pet off the Apothecary vendor.
Alliance will need to complete a quest chain which involves killing Jor’kil the Soulripper for a loot item. This item will start another quest which unlocks Remembrance of Auberdine.
You’ll notice that whenever his minion gets too close he punts him away with a swift kick… reminds me of a rogue I used to know who would never fail to punt that NPC in UBRS.
Upon summoning this companion, it is surprisingly large for a non-combat pet, but over time it will shrink to the size of the Teldrassil Sproutling. If it’s near a body of water while in its smaller state, it will emote “Withers absorbs the water, growing back to full size” and grow back to its original size.