Call the Midwife star on Sister Monica Joan's fears in Christmas special

"One should recognise there are a lot of people in the population who are older and just feel that they’re never going to make it through [the winter]," she explained of the episode.

"And this to an extreme extent [means she] feels she's not going to make it through, so it's a matter of everybody pulling together and getting around that."

McGann added that these fears lead to a "rather lovely community spirit" developing – something which he believes is especially important to portray during the festive period.

"It is hard in winter," he said. "My mum is elderly now - 88, 89 - and we were talking about Christmas. And she’s up in Liverpool and she can't get around so much anymore.

"And at that age, you can be up and down. You can look at your life. And it's one of those times of the year when, although she has a wonderful community there and one of my brothers lives up there, it's still one of those times where she reflects and it's hard."

He added: "It's a difficult time of year. And so when we have a character like brilliant Judy Parfitt, you have the unique opportunity to express Christmas also through elders and through reflections of [how] life has been for people.

"And all these ordinary families who will be watching at Christmas look at a community that in some way resembles their own hopes and fears."

Read more:

• Call the Midwife shares emotional first look at Christmas special
• Call the Midwife star teases "dangerous, high-drama" snow in Christmas special

Fans were given an emotional first look at the special when the BBC released a preview clip at the end of November, which showed Sister Julienne comforting a tearful Shelagh Turner (Laura Main).

In the clip, Shelagh reveals she has received a package from Hong Kong from her adopted daughter Mae's biological mother and hasn't even told her husband, Dr Patrick Turner (Stephen McGann), about it – with the ever reliable Julienne then providing her with some wise advice.

The official synopsis for the episode reads: "Call the Midwife’s Christmas Special begins two weeks before Christmas, with Apollo 8 poised to circle the moon.

"Sister Monica Joan (Judy Parfitt) is convinced this could be her last yuletide, and decides she’ll not live to see man walk on the moon.

"The Nonnatus Family, including Trixie (Helen George)’s brother Geoffrey (Christopher Harper), decide something must be done to try and lighten her state of mind.

"Nancy (Megan Cusack) has recommitted to staying at Nonnatus House and Sister Julienne (Jenny Agutter) has offered her and Colette (Francesca Fullilove) a room for the foreseeable future.

"Trixie and Matthew (Olly Rix), fresh from their honeymoon, are preparing for their first Christmas together as husband and wife when Geoffrey pays them an unexpected visit days before Christmas."

It continues: "Cyril (Zephryn Taitte) gently intervenes when he discovers a lost soul living alone in a dilapidated basement flat. For this man, Christmas is a reminder of all he’s lost and all he’s never had.

"Nurse Crane (Linda Bassett), away on her refresher course, makes it home in time for Christmas festivities despite a treacherously heavy snowfall."

The Call the Midwife Christmas special will air on BBC One on Christmas Day, and all 12 seasons of the show are available to stream on BBC iPlayer. If you're looking for more to watch, check out our TV Guide and Streaming Guide or visit our Drama hub for more news and features.

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