Call the Midwife star on Miss Higgins's grandson: 'She’ll never be the same again'

In time, they had a son, but due to the taboo nature of their relationship, he was given to another family and that was the last she saw of him – that is until Miss Higgins was reunited with her child in Poplar last season, where she was overjoyed to learn that his son, Harry, is studying in Liverpool.

"When I did interviews after the storyline last year, I sort of said it was like a little spotlight had shone on her past, and then it would go out again and life would carry on as normal," Glen told RadioTimes.com and other press.

"And I realised as soon as I came back, of course it can't carry on as normal, that I'm actually the same person, but in a very different position now because a few people are privy to it, Dr Turner and Nurse Crane, and I'm never going to be the same again because a fundamental change has happened in her life."

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Glen went on to say that for Miss Higgins, it's now about navigating "a new reality within that new discovery because... she's lived a long life just with the grief and the memory of what happened".

"And although her son has now died, she has at least been reunited with him and she has gained his son, and her life is enriched by that," added Glen.

"It's changed her life completely."

This year's Christmas special, which is the first double festive episode in the show's history, picks up in 1969.

The midwives are "all busy delivering babies and doing the job they are most dedicated and committed to", while Poplar also welcomes a funfair, which adds "a burst of colour and excitement to the frosty landscape".

But there will be challenges, including influenza and the Hong Kong flu, not to mention an escaped prisoner.

As the neighbourhood prepares for a carol concert, "fears grow that he may be in the local area after a spate of break-ins".

Elsewhere, "the Turner children are caught up in the fever surrounding the Blue Peter Christmas appeal to collect dinky cars and scrap metal, Trixie makes a fleeting visit to Nonnatus House and is delighted to see her brother Geoffrey, and Miss Higgins has her grandson Harry stay for Christmas".

Violet also has her hands full hosting a mince pie competition, "but the Buckles' preparations for Reggie’s homecoming are thrown into turmoil".

Call the Midwife returns to BBC One and iPlayer this Christmas.

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