Introduction Etiquette and Sisters

If the three should be together and there was a desire to introduce them, the form would be to present the elder as Miss Smith and the other two by their given names.

If there are three sisters in a family named Smith and a call is made at their home, if Miss Smith is asked for, it is supposed that the elder sister is desired; the others if desired, are called by their given names. If met individually it would be proper to address either as Miss Smith. 

If the three should be together and there was a desire to introduce them, the form would be to present the elder as Miss Smith and the other two by their given names, in addition to the family name. That is the rule if you follow etiquette, but if you do not follow that, then you may introduce the sisters each by her given as well as family name. – San Francisco Call, 1901

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