Isabel Getty is the ultimate cool girl bride for her Chelsea Town Hall wedding

Pia, a recent grandmother, makes up one-third of the Miller sisters, the ultimate Park Avenue Princesses in the ‘90s. Three years after Pia married Christopher in 1993 (in Bali, no less), her sister, Marie-Chantal, tied the knot with Crown Prince Pavlos of Greece; three months after that, her sister Alexandra married Prince Alexander von Fürstenberg, son of the designer Diane and the great-great-grandson of Fiat founder Giovanni Agnelli.

‘Civilly civil,’ she wrote in an Instagram post…