" But this can be purely philosophical: 2) If you take the two words (maternal and aunt) separately: "maternal" means related through a mother , which makes the wife of a mother's brother a maternal aunt as well . If you go with this philosophy, then many many people can be related through a mother and any remote and tangential relation can be considered as maternal (provided it is a relation that somehow comes into place through the mother)! In general though, a "maternal aunt" should be seen as in 1) above-- that is to say, there should be DNA or blood relationship though the mother.
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