Answer (1 of 4): Well, I don't know how this sister sizes ( in relation like sister companies etc,,) ever became as you describe..There is nothing remotely close to each of those sizes. Mathematically and according to any standardized charts ..Remember one very important rule in life .Mathematics
Explaining Bra Sizes - What are Sister Sizes? :: Beauty and Clip in Hair Extensions News - Undercover Glamour
Bra Sister Sizes + Sister Size Chart
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