Nearly 3 million people across the world tuned into her younger sister's nuptials in 2018.
The never-before-seen pictures include a shot with her "Big Little Lies" co-stars and a much-awaited look at her wedding dress.
170,000 people are expected to tie the knot from New Year’s Eve following a change in the law.
Her parents had left early to arrive at the venue, but were in a car crash which meant they were delayed.
Myles Harrison, 27, married fiancee Liz, 29, at a ceremony Castle Hill in Filleigh, Devon, with their whole wedding donated by well-wishers.
"She's hijacking the wedding to feel like the bride."