The actress, known for her role as Lady Sybil Crawley in the ITV period drama, took to Instagram with a photo of the couple embracing on their big day, as well as another of the pair inside of the church where they said 'I do'.
She captioned the former, "[Heart emoji] wins every time. A weekend of dreams. Small celebrations felt HUGE. And now what a birthday X I love you. [Heart emoji]."
The photo, shot in black and white, showed Jessica and Ziggy hugging outdoors, with Jessica wearing a high-neck lace gown and a jewelled headband with her hair swept back in a bun, and Ziggy sporting a patterned waistcoat, a white shirt and black trousers.
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A second shot in the carousel showed Jessica on her birthday, in what seems to be a beautiful hotel room, where the couple have likely chosen to spend a mini-moon while the coronavirus pandemic continues and they are unable to travel for a more lavish honeymoon.
An image shared on her Story, meanwhile, revealed that the couple opted for a church ceremony, with the stunning venue featuring grand high ceilings, classic wooden pews at either side of the aisle, and large chandeliers hanging overhead.
Jessica married fellow actor Ziggy Heath
It also revealed more detail of Jessica's dress, including a sweeping tulle skirt and a matching veil. Ziggy completed his look with a matching black suit jacket and a cream corsage. Jessica wrote, "We did it," and confirmed the date of their nuptials, "12.09.20."
The couple met on the set of BBC series Harlots in 2017, and have been dating ever since. Jessica took on the role of Charlotte Wells in the drama, while Ziggy played Sam Holland.
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