Stepping out on Sunday, the late Queen Elizabeth II's granddaughter, 20, looked every inch her mother Duchess Sophie's style muse wearing an elegant silk twilly scarf from Parisian label Hermès.

She customized those herself. The long scarf tied to Witt’s purse was a gift to the wives from Wacha. It is a twilly, a long, narrow, silk scarf that can serve as a hair accessory, tie ...