by ACThere
You have three named characters and picked "Kathy" and "Kathleen" for the two females? Kathy is actually a common shortening of Kathleen, so basically you gave them both the same name...
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You can take my word for it or you can research it yourself, but some basic writing advice is to make sure that you don't give different characters similar names. It makes it hard to keep them straight. For this reason, many experts advice writers to give each character a unique first initial. If you're writing a huge novel, restrict that advice to the main characters. Background and throwaway characters can share initials with each other, but not the main characters.