Doctor Who: Ranking The Weddings Of The Whoniverse
6. Prem And Umbreen (Demons Of The Punjab)
A supposedly simple trip to the past to learn more about Yaz's Grandmother, Umbreen, quickly becomes complicated for the Thirteenth Doctor and her Fam when they realise they have arrived the day before the partition of India. They become even more complicated when Yaz learns that the young Umbreen is about to marry Prem, a man who is definitely not Yaz's Grandfather.
Still, to keep Yaz's timeline in tact, the Fam are caught up in the effort to ensure the interfaith wedding (Prem is Hindu, while Umbreen is Muslim) goes ahead. Unfortunately, the group soon learns that Prem will soon meet an unpleasant fate, explaining why Yaz never knew about Umbreen's first marriage.
In a bittersweet scene, The Doctor marries Prem and Umbreen in a beautiful ceremony, just hours before Prem is destined to be killed by his own brother, Manish, a supporter of the partition.