Once your teen hits puberty, she will probably add "developing breasts" to the laundry list of changes that she is experiencing. She might even find that asking.
Bra shopping with your preteen or teen can be tricky to navigate It doesn't have to be a THING. The only “should” for your kid's first bra?.
to What Type of Bra Should Teenagers Wear? by Kay Ireland, there In other words, training bras are designed with three things in mind.