Precision marching is less important for the bridal party than maintaining the proper facial expressions: The bridegroom must look awed; the bridesmaids, happy and excited; the father of the bride, proud; and the bride, demure. If the bridegroom feels doubtful, the bridesmaids, sulky, the father, worried, and the bride, blasé, nobody wants to know.

Judith Martin (b. 1938) American author, journalist, etiquette expert [a.k.a. Miss Manners]

Miss Manners on Painfully Proper Weddings, ch. 1 “General Principles” (1995)
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Caption for an illustration of the Processional.

Book also titled in later editions Miss Manners on Weddings and Miss Manners' Guide to a Surprisingly Dignified Wedding.