When Call the Midwife's Patrick (Stephen McGann) and Shelagh Turner (Laura Main) agreed to foster a young Chinese orphan called May (April Rae Hoeang) whose planned adoptive family fell through in season eight of the BBC period drama fans were delighted to see their family expand.

She brought the number of their brood to four comprised of Patrick's oldest son Timothy (Max Macmillan) from his first marriage, adopted daughter Angela (Alice Brown) and their biological son Teddy (Edward Shaw).

Speaking exclusively to Express.co.uk Stephen McGann revealed there was a very touching reason her adoption was written into the programme as the show's creator, his wife Heidi Thomas, felt young Alice needed a friend on set.

"One of the things at the back of Heidi's mind was little Alice, who used to be there from a toddler upwards, sometimes you'd look at her, and it's a terrible place to be a TV set, and she'd be on her own.

"And although me and Laura were very friendly with her... Heidi said, 'apart from everything else, I think she could do with a little friend on set'," he said.

Having decided on the adoption storyline April was hired to play the newcomer and Stephen revealed the young cast members immediately bonded.