The Legend of Zelda: Twilight Princess Tips

Yet another heart piece.
About 3 quarters through the game you shall come across an abandoned town called the hidden village.

After you have completed everything relating to the storyline here, you should leave and come back straight away as a wolf. Go through the houses to the right of the town and talk to the Cucoo (chicken) to initiate a mini-game where you must talk to each cat in the village (20 in all I think)if you complete this then you are rewarded with a piece of heart.

(NOTE) The is a howling stone directly across from the chicken in the hidden village.