At what age should a girl begin to shop in Victoria's Secret?

My daughter is 13 and some of her friends (and older sister 19, and 23) have been wearing the PINK line. She really wants to wear the shorts, yoga pants, bras etc. I just don't know how I'd feel about that. Not to mention she's very tiny and thin and the clothes would NEVER fit her unless they were altered. She's 4'8'', 77lbs, and size 10 slim. She really wants to be able to shop in there, like her friends but I'm afraid she may want to try to grow up too fast. I recently started letting her get the PINK line of body wash and lotions at bath and body works. She loves it. I also let her get a Pink hoodie that had a peace sign on the back like the one's she finds from Justice. The VS size XS is just huge on her. She asked for a bikini from VS but there just isn't anything there that we find appropriate for a child. I also don't find the underwear appropriate. I have been thinking about getting her a couple of the solid sports bras and taking them in on the sides, but I know she really wants to get a " real bra" from there. How far is a 32AA from a 28AA? I just want her to be able to feel a little more her age, its hard for her since she's so small, people often treat her younger and I just want her to feel good about herslef. will this help her? is 13 a little too young to shop in VS PINK or should we just stick to JUSTICE until she grows a little bit? thanks