Which of the following is accurate in British English to describe our own wedding?

  1. Alex and Jen's Wedding
  2. Alex's and Jen's Wedding
  3. Alex and Jens' Wedding

Solution 1:

If Alex and Jen are marrying each other, then it is "Alex and Jen's wedding". If somehow they are marrying two other people, then it is "Alex's and Jen's wedding".

This distinction becomes more significant when the possession is also plural.

Alex and Jen's cats are the cats owned jointly by Alex and Jen.

Alex's and Jen's cats are the cat or cats owned by Alex plus the cat or cats owned by Jen.