Karen Baldwin (The Time Travellers)
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Karen Baldwin was a British medic.
Originally, she met the man who would father their only child together, Louise, in 1975. She gave birth to Louise in 1976.
However, due to alterations in the timeline, Baldwin was killed in 1972. An older version of Louise travelled to that year from an alternate future and became trapped there. This meant she lived the rest of her life in a world where she had never been born. (PROSE: The Time Travellers)