Call the Midwife S15 forewarns tragic Sister Monica Joan's departure as she's diagnosed with potentially fatal illness
There's heartbreak ahead
Call the Midwife fans have every reason to be worried about the BBC One show’s eccentric but (usually) lovable Sister Monica Joan as illness plights her health once again.
In Sunday night’s episode of the period drama (Sunday, February 08, 2026), Dr Patrick Turner diagnosed her with a potentially life threatening condition.
Of course, Judy Parfitt has played Sister Monica Joan ever since the first first series in 2012. And, in real life, she is 90 years old. That makes her by far the oldest actress – and character – in the show.
Some references suggesting the elderly nun is close to 100 years old at this point. So is Judy Parfitt leaving Call the Midwife, as the future of Sister Monica Joan looks dicey?
Here’s what we know.
What is wrong with Sister Monica Joan? What illness does she have?
In the latest episode of Call the Midwife series 15, Sister Monica Joan was off her food – even cake! – and lost in reminiscence. While washing her, Sister Julienne discovered Sister Monica Joan’s feet were incredibly swollen. Sister Monica Joan said it was “a recent development” and insisted “they not speak of it”.
Dr Turner subsequently made a house call on Sister Monica Joan, and made a devastating diagnosis – kidney failure. In response to the news, Sister Julienne told the doctor: “This was always going to come, wasn’t it? In one form or other.”
Doctor Turner responded: “And, when it does, it’s going to feel like the Ravens leaving the Tower of London. The end of the known world.”
Yes, Patrick, we couldn’t have put it better ourselves. Of course, we already knew that elderly Sister Monica Joan faces ongoing health challenges, including failing eyesight, forgetfulness, and general frailty.
And, as she awaits further tests, fans will no doubt be concerned about the beloved long-standing character.
Is kidney failure fatal?
Kidney failure can be fatal, if left untreated. The body fills with toxins and excess fluid, which can lead to severe complications like heart damage, seizures, or coma.
However, it is manageable through dialysis or a transplant, allowing many people to live for years. But, with Sister Monica’s old age, it’s unlikely she would survive a transplant.
Does she have dementia?
Sister Monica Joan is suffering from the early stages of dementia. She is also very frail in body. Desperate to still be of service to The Order, her friends and fellow nuns give her easy tasks to do to keep her occupied and feeling useful.
Talking about her character, Judy Parfitt has said: “She’s very eccentric but she’s also getting dementia. So she’s in and out of reality which makes it really interesting to play because it’s a very difficult line to get through.”
In real life, Judy Parfitt herself is a campaigner for the treatment and awareness of dementia. Her late husband, the actor Tony Steedman, suffered from dementia for five years and died from it in 2001.
Is Judy Parfitt leaving Call the Midwife?
BBC One has not confirmed if Judy Parfitt’s character Sister Monica Joan is leaving the period drama. But fans know the departure must surely be on the cards in the near future.
Of course, fans of the show know that Call the Midwife is taking a break after series 15 for a prequel series and a movie, but the BBC has confirmed the show will return for a 16th series. Whether Judy Parfitt will be part of the cast remains to be seen.
We do know that a younger version of Judy Parfitt’s Sister Monica Joan will be the focus of the upcoming prequel. Series creator Heidi Thomas confirmed the three lead characters would also follow the younger versions of Sisters Julienne and Evangelina, played by Jenny Agutter and Pam Ferris in the original show. Younger actresses, as yet unnamed, will be playing the characters.
Fans are rightly concerned for the future of Sister Monica Joan. One said on Reddit: “I think the final episode will be Sister Monica Joan’s death and funeral. This will coincide with the closure of Nonnatus House. What I’d really like to include is bringing back as many of the former midwives as possible: Jenny, Cynthia, Chummy (and Peter), Patsy, Valerie, Lucille, Nancy (and Colette), sister Hilda, and sister Francis.”
Another doesn’t want the elderly nun to be facing illness. They said: “Now it seems that the writers are focusing on her old age and approaching death. I wish they wouldn’t. I wish the writers would portray Sister Monica Joan as a still formidable presence in the convent. I know she can’t work anymore, but let her be an inspiration to the younger midwives.”
Who is Sister Monica Joan?
Sister Monica Joan remains a beloved, eccentric figure at Nonnatus House in Call the Midwife. And she’s lived a virtuous and pious life.
Born into a leading titled family, Sister Monica Joan was one of the first women in Britain to qualify as a midwife. In the closing years of the 19th century, this was seen as a radical act. Her additional decision to become a nun scandalised her relatives, who never came to terms with her life choices. Damned if she cared!
She dedicated her entire adult life to providing midwifery services to the poor of the East End. Now in her nineties, Sister Monica Joan has retired from practice, but lives full-time at Nonnatus House, cared for by her fellow sisters.
Recently Sister Monica Joan has grown increasingly frail and questioning of her usefulness at Nonnatus.
