Toddlers in the $600 High-Tops Luxury labels are aimed at children, and parents are purchasing.

Taylen Biggs was captivated to the vivid hues of her first runway displays. "I was quite young, so I didn't understand anything," she admitted. Taylen, a preternaturally articulate young woman with a high, tight ponytail and immaculate manners, was four years old at the time. Taylen...