Princess Beatrice of York
A small number of guests were also there, Buckingham Palace has confirmed.
It'll be a spring ceremony for Prince Andrew's daughter and Italian real estate magnate Edoardo Mapelli Mozzi.
The wedding will take place in 2020, Prince Andrew and the Duchess of York said.
The sisters have been in the eye of fashion watchers since they were babies. As they've grown, they've also been the subject of tabloid fodder and criticism.
