Most preteen girls will experience breast buds between the ages of 8 and 11, but it's not uncommon for the development to begin earlier or later. It's at this phase when many girls ask for a training bra, or begin wearing camisoles under their clothes.
Stage two (breast buds) may last several months or for a year or more. Girls may become self-conscious during this phase, especially if their friends have not yet developed.
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