Answer:
superseding cause
Explanation:
According to my research on different liability law suits, I can say that based on the information provided within the question Iris will not be liable for this second set of injuries because the plane crash was a superseding cause. This refers to an accident that happens after another (initial accident) has already occurred in which an injury has happened. In this type of situation the person who caused the initial accident is not responsible for the second accident or injuries caused by it.
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