From Halopedia, the Halo wiki
Katrina is a former resident of Elysium City on Eridanus II. She knew John, the future Master Chief, prior to his abduction. Benjamin Giraud interviewed her as part of his series of biographical interviews about John-117 in 2558; she was a childhood friend of fellow interviewee Ellie Bloom.
Katrina recounted having watched John (or what was in actuality John's flash clone) die of an unknown condition in 2517, and insisted that John's parents were alive and well in Elysium City until at least 2528. Both claims were in conflict with the accounts of Gabriella Dvørak and the purported Deon Govender, (really an ONI-employed actor) who claimed that John's parents had died before the liberation of Elysium City in 2524, and that John was alive and living there at that time.
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