Problem is, I easily found a scenario that breaks the chart. Say that I am "Ann" and my son is "John" - using the chart and fitting in our names we get: If one person [Ann's] parent is the other person [John's] grandparent, then they are Niece/Nephew or Aunt/Uncle. Well, no, that's only true for one of my sibling's kids and myself. Quibble, quibble.
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