Hello Breez The use of "they" for "he or she" and "their" for "his or her" (or where the *** of the referent is unimportant or unknown) is very common. It's by no means a new usage; it dates from at least the 13th century, and can be found in the works of many significant writers. Here are some examples of "their" in place of "his or her": 1.
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