Extract and list the names of characters a player can control in The Last of Us mentioned in the paragraph. Also describe relationships between those characters.

The Last of Us is an action-adventure game played from a third-person perspective. The player traverses post-apocalyptic environments such as towns, buildings, forests, and sewers to advance the story. The player can use firearms, improvised weapons, hand-to-hand combat, and stealth to defend against hostile humans and cannibalistic creatures infected by a mutated strain of the Cordyceps fungus. For most of the game, the player takes control of Joel, a man tasked with escorting a young girl, Ellie, across the United States. The player also controls Ellie throughout the game's winter segment and briefly controls Joel's daughter, Sarah, in the opening sequence.

In the Last of Us, a player can control Joel, Ellie (who is being escorted by Joel across the United States), and Sarah (who is Joel's daughter).