My preteen sister is starting to be interested in fashion and seems to be making some bad choices. Any tips on how to guide her?
—Jennifer, via the Ask Style inbox

You're a good sister. You know who needs a sister like you? Noah Cyrus, 9-year-old sibling of the much better known Miley. She traipsed down a red carpet the other day in a black-and-purple micro-mini with matching lace-up boots. Yes, it's October, but even Halloween is no excuse for proto-slutdom among the tweens.

Let's give Noah and your li'l sis a makeover, shall we? And let's make them shop on an allowance while we're at it. Children, we're going to Target. 

There's no reason a tween girl can't wear a short dress, provided it's age-appropriate, like a rose-print sleeveless number that hits mid-thigh. It has all the tulle and ruffles a kid likes, without dipping into weird goth territory.

Tank dresses can also be fun; they're simple and streamlined enough that you can load on the metallic ruffly accessories, which young girls also adore.

As for shoes, leave the '70s rock up-to-there black boots for the older sisters, kids. (A tall boot is not out of the question, of course, just the '70s rock up-to-there black boots.) And if flats are good enough for big-girl fashionistas, why not try a metallic ballet flat? It goes with everything—even red carpet tantrums.

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