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http://heroeswiki.com/Charlie_Andrews
Charlie's birthday was "about six months ago" (April 24). When Hiro went back in time in an attempt to save her, he gave her a Japanese phrasebook as a birthday present. However, Charlie had also received a Japanese phrasebook for her birthday in the original timeline. Since Hiro was not at Charlie's birthday party in the original timeline, it is unknown who gave this phrasebook to her (it is possible that this is a Predestination Paradox, although this would raise the question of why Hiro did not appear in her birthday photo until he went back in time).
While Charlie's formal name is not fully shown on the list, Mohinder says that "Charlene Andrews" was killed "two days ago, Midland, Texas." (Fallout)
Sylar uses the enhanced memory he stole from Charlie to memorize a truck's instruction manual.