Hollywood’s hottest moms have ruled the red carpet this past week, during the 64th Annual Cannes Film Festival at Palais des Festivals. From plunging necklines to glamorous gowns and brilliant jewels, these leading ladies brought the sexy to the French coast. Gwen Stefani, with hubby Gavin Rossdale, takes the plunge in a black sequins jumpsuit by Stella McCartney Milla Jovovich looks exquisite in a Prada gown and has fun showing off over 90 carats of jeweled delights from Jacob & Co…