Madam Marsh was an elderly witch who seemed to suffer from motion sickness. She frequently rode on the Knight Bus, nevertheless, suggesting she travels a lot.
In 1993, she travelled on the Knight Bus at the same time as Harry Potter. She got off the bus at Abergavenny looking queasy. 
In 1996, Madam Marsh was seen travelling again on the Knight Bus. This time she became sick and vomited. She was let off before Harry, Hermione, and the Weasleys. 
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