The sixth season finale of "Call the Midwife" is about to air on PBS on Sunday, which means fans should expect to shed a lot of tears for the major events that are about to unfold in the series.

According to the synopsis of episode 8, a surprising turn of events will be the reason why a wedding will be rapidly arranged.

Speculations claim that Nurse Barbara (Charlotte Ritchie) will panic when she finds out that her Vicar father will be assigned in an overseas mission, which means he will not be available to officiate her wedding with Reverend Tom Hereward (Jack Ashton). This will force her to get married earlier than planned. However, this means that she will only have several weeks to prepare for the wedding.

The synopsis also reveals that the upcoming season 6 finale will feature the upcoming childbirth of Shelagh (Laura Main) to her new child with husband Patrick Turner (Stephen McGann).

The episode will also reportedly feature the return of Patsy Mount (Emerald Fennell) to Poplar from Hong Kong to be reunited with girlfriend Delia Busby (Kate Lamb).

The episode is scheduled to air on PBS on Sunday, May 21, at 8 p.m. EDT.

Meanwhile, the cast and crew of "Call the Midwife" have already begun with production of the show's season 7.

In an interview with Radio Times during the BFI and Radio Times Television Festival, McGann hints that the characters will face more challenges next season. He also shares what fans should look forward to in Dr. Turner's fate in season 7. "I think there's going to be beehives and it isn't going to be Doctor Turner. I don't think I can carry the beehive off, but we're getting closer to your classic sixties look."

McGann also claims that the next installment of the British period drama will center on the events that happened in 1963, which also happens to be the year of his birth.