Doctor Who reveals identity of Ruby Sunday's mother after season-long mystery

It's a question that has plagued Millie Gibson's character and audiences for the entire season, after we first met the companion in the 2023 Christmas special The Church on Ruby Road.

There have been theories galore, with many wondering if Ruby's mother is someone we already know or a character who has appeared in Doctor Who before.

But, actually, Ruby's mother is an ordinary - but very important - woman named Louise Alison Miller, played by Faye McKeever, who fans might recognise as Linda in Sky sitcom Trollied, Marie in the BBC Three series Massive, or Claire Olssen in ITV drama Little Boy Blue.

After defeating Sutekh and bringing life back to the universe, Ruby, the Doctor and Mel Bush (Bonnie Langford) return to UNIT HQ, where they're able to trace Ruby's DNA to her mother.

"Louise Alison Miller," Morris (Lenny Rush) tells Ruby. "Thirty-five years old, 15 when she gave birth to you."

Kate Stewart (Jemma Redgrave) adds: "Records say her stepfather... well, he was trouble. I think she did the right thing getting you out of that house."

Rose Noble (Yasmin Finney) goes on to say: "She must have hidden the pregnancy."

Kate adds that the identity of Ruby's father is known, and then goes to on to say that Louise is a nurse.

Ruby is left stunned at how "ordinary" her mother is, wondering how she stayed invisible from Sutekh.

"She was important because we think she's important," the Doctor says. "That's how everything happens - every war, every religion, every love story.

"We invest things with significance. So while the whole of creation was turning around her, it made her sheer existence more powerful than Time Lords and gods.

"In the end, the most important person in the universe was the most ordinary. A scared little girl making her baby safe."

With Rose reminding the group that Louise pointed at the Doctor on the night she left Ruby at the Church, the Doctor reveals she wasn't actually pointing at him, but at the road sign for Ruby Road, effectively giving Ruby her name.

The Doctor and Ruby go on to visit Louise, keeping a distance from her as they watch her from outside a coffee shop.

"She has had over 7,000 days to come and find you and she never has," the Doctor tells Ruby. "Louise will have made her choices and I think we should leave that alone."

But, after so many years of wondering, Ruby can't leave it there. She orders a coffee and, when her name is called, reveals her identity to Louise in an emotional exchange.

The pair share a hug, and we later see Louise at home with the Sundays, poring over photos of Ruby's childhood.

By the end of the episode, not only has Ruby reunited with her birth mother, she's on her way to meet her biological father.

The Doctor also reveals that she's changed his perception of family, and made his life bigger and better - even leaving the door open for a visit to his granddaughter, Susan Foreman (Carole Ann Ford).

Doctor Who will return to BBC One and BBC iPlayer in 2025. Previous seasons are available to stream on BBC iPlayer.

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