The flower girl chosen for the wedding is usually a younger bridesmaid. She will carry a basket of
flowers or flower petals. At the wedding, the flower girl joins in the procession with the other attendants and then walks back down the aisle in front of the happy couple strewing
flowers in their path (you should check with the venue whether this is allowed).
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Other useful Flower girl resources:
From the younger girl's point of view, she may want to be dressed the same as the older
bridesmaids. Alternately, she (and you) may want her flower girl dress to be as 'fairytale' and dramatic as possible.