Ilia

Ilia is the daughter of Mayor Bo of Ordon Village, whom says that she is the spitting image of her late mother. She is Link's childhood friend in The Legend of Zelda: Twilight Princess. She wears a white, sleeveless dress shirt, light brown, half-length pants, and a dark brown pouch on her leg. She is about 16 years old, which would her the second oldest youth of Ordon after Link.

She can loosely be considered the game's equivalent of Malon as she has a strong connection to Epona.

The Legend of Zelda: Twilight Princess
In The Legend of Zelda: Twilight Princess, Ilia is first seen taking Link's horse Epona to bathe at Ordon Spring after he returns home. If Mayor Bo is visited in Ordon Village the next day, he will mention that she locked herself in her room to work on something and refuses to see Link at the moment. The following day, she notices that Epona apparently has an injury on her hind leg, and chastises Link for pushing her too hard again for jumping fences as well as her father for being too soft on Link, then immediately walks Epona to heal at Ordon Spring. After Colin explains that Epona probably got hurt while saving Talo, they are suddenly attacked by King Bulbo's band of Bulbins, and she is knocked unconscious when struck by an arrow. When Link awakens, he attempts to follow but ends up in the Twilight Realm. Later, after Midna meets with Princess Zelda, she assumes the visage of Colin and Ilia screaming to motivate Wolf Link.

Off-screen, Ilia was taken captive along with Impaz in the hidden village, whom she befriended. Ilia spoke highly of Link's courage and reassured her that he would come rescue them. Ilia entrusted Impaz with the charm that she had finished working on to protect her, and Impaz helped Ilia escape. She finds a Zora boy collapsed on the road, who turns out to be the recently-orphaned prince Ralis, and takes him to Hyrule Castle Town.

When visiting Lanayru Province for the first time, Wolf Link can find the Scent of Ilia from a discarded pouch on the ground, which ends at Telma's Bar. Once Hyrule Castle Town is purged of twilight, Link finds that Ilia is interested in taking Ralis to a shaman in Kakariko Village that has cared for Gorons and Zoras. Telma reveals that although Ilia lost her memories and cannot even remember her name, she had been more worried about Ralis' health. Link escorts them to Kakariko Village, where Ralis receives treatment by the shaman Renado, and she remains there under his watch. A vision depicting Ilia is later used by Lanayru to represent a Hyrulean; after she witnesses the goddesses with Link, she becomes blinded by greed caused by the Sacred Realm and attempts to stab him with a knife, but it is implied that she is preemptively struck down by Link, who then becomes blinded himself and runs toward the Triforce. At the end of the vision, there are multiple Ilias falling upside-down while giggling ominously.

Link can optionally return the charm to Ilia after retrieving it from Impaz. The sight of it restores her memory, and she says that she had intended to give it to him before his and Epona's journey to Hyrule. This reveals the purpose of the charm as a horse call that Link can use to summon Epona without having to snatch a reed whistle. Regardless, Ilia returns to Ordon Village along with the other children during the game's ending, and is last seen standing by herself, implied to have seen Link and Epona off on their next journey.

Super Smash Bros. Brawl
In Super Smash Bros. Brawl, a trophy of Ilia can be obtained in the game randomly.

Hyrule Warriors
While Ilia does not make a direct appearance in Hyrule Warriors, Ilia's Clothes (and hairstyle) is available in the downloadable Twilight Princess Pack as a costume for Zelda. In Hyrule Warriors: Definitive Edition, as with all the other downloadable content in Hyrule Warriors and Hyrule Warriors Legends, this costume is unlockable within the base game.

The Legend of Zelda: Twilight Princess

 * Prima Games: "An attractive young woman of about 16 years, Ilia is the charming daughter of Bo, the mayor of Ordon Village. Beloved by all who know her and fast friends with Link, Ilia is always cheerful and active. Even after falling victim to severe memory loss, Ilia’s kind and gentle nature never changes."

Trivia

 * Like the other NPCs of Ordon Village, Ilia has round ears and appears to have no obvious Hylian lineage; however, she is shown to have Hylian ears in concept art, as well as one version depicting what appears to be Navi on her forehead.
 * At the beginning of the cutscene where Link finds Ilia approaching Epona in Ordon Spring, she eyes Link's direction before focusing her attention on Epona. This cannot be seen in normal gameplay, as this happens while the camera pans from Link.