How many are there in Mi-na's family? There are five in her family: her mother, her father, her older brother,Min-su, her younger brother Min-ho and she/her.

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Do I have to use 'she' or 'her' at the end of the second sentence?
Ae the expressions above correct?

Use "herself" at the end of the sentence. I've tried it all three ways (with "she," "her," and "herself"), and the last one sounds most fitting.

Delete comma after "older brother" and insert comma before and after "Min-ho."