Beatrice and Eugenie are very close, undertaking charity and royal engagements together, and mixing in the same friendship groups, so Princess Beatrice is the key contender for maid of honour duties.
Beatrice was in a relationship with Uber executive Dave Clark for almost ten years, and they double dated and holidayed with Eugenie and Jack on many occasions. However, although Beatrice has been romantically linked to oil heir Michael Hess, she hasn't gone pubic with a boyfriend since her breakup in 2016. This means she's likely to buddy up with her mum, Sarah Ferguson, who has been in on-and-off relationship with businessman Manuel Fernandez since 2014.