what is the true definition of "mirror twins"

[emmacherise2]

myself and identical twin sister believe we are mirror twins. our hair parts on different sides, i'm right handed she's left.. im very academic wheras she's more creative, i cross my arms with my right hand on top and she does with her lieft hand on top etc etc.. it goes on. i was wondering what the true definition of mirror twins is.. as it seems to be a very grey area. thank you

[Ethel]

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