From Halopedia, the Halo wiki
Teddy was an agent of the Office of Naval Intelligence responsible for abducting children for the Spartan-II program. In 2517, he was on Cascade and abducted a half-starved Serin Osman in St. Malo after luring her away with a hamburger. ONI did not bother to replace Serin with a flash clone as she was already being neglected by her junkie mother.
Decades later, Serin Osman would frequently experience nightmares about her abduction and would sometimes think about what became of Mr. Teddy. She assumed that he likely perished during the Human-Covenant War. Having now risen to CINCONI, Osman had the means to find out if he was alive and well, but chose not to, out of fear that she might want to retaliate against him or any of his loved ones.
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