Ilari

From Zelda Wiki.org

Ilari is a Windfall Island postman from The Wind Waker. He was born on Dragon Roost Island and is a Rito. He is quite kind as long as he's composed, but when things don't go well, he quickly grows impatient and can get rough with his speech. He apparently has a hard time remembering people's faces.

On Windfall Island, Ilari and Maggie's Father are fighting about a letter that was sent to the newly-rich home-owner's house that he didn't want, even though it was a letter for Maggie. To get a Piece of Heart you need to go to the Milk Bar and talk to Ilari and he will let you deliver the letter to Maggie.