Steven Spielberg's step-daughter took to Instagram on Saturday (06Dec15) to announce the happy news that she and her husband Christopher Gavigan will welcome their latest addition next year (16).

"The holidays have certainly arrived," Jessica wrote. "All of our lives are being added to by the lights, music and the cheer!! This year our family has reason to further broaden our number four is on the way!! I am a lucky, lucky girl."

Jessica and Christopher are already parents to daughters Poppy, three, Eve, five, and son Luke, eight.