Grace O'Brien was the paternal grandmother of Ryan Sinclair. She lived in Sheffield with her second husband, Graham O'Brien.
Biography
Grace was interested in the American Civil Rights Movement and was inspired in particular by the deeds of Rosa Parks and Martin Luther King, owning a t-shirt that said "the Spirit of Rosa". (TV: Rosa) Grace loved watching period dramas with posh country estates on telly. (PROSE: The Secret in Vault 13)
In 2012, after his mother passed away, Grace came to raise her grandson, Ryan Sinclair. (TV: The Woman Who Fell to Earth) She told him the fable of The Lion and the Mouse, (PROSE: The Good Doctor) and would often attempt to teach Ryan how to ride a bicycle, which he struggled with because of his dyspraxia. (TV: The Woman Who Fell to Earth)
Grace worked as a chemo nurse. It was during this line of work that she met cancer patient Graham O'Brien, whom she become attracted too. (TV: The Woman Who Fell to Earth) When she learned that Graham was a bus driver, she remarked that he ought not to be like James Blake, who she called "Blake the snake". (TV: Rosa) After his cancer went into remission, Graham and Grace married. (TV: The Woman Who Fell to Earth)
Death
In September 2018, whilst returning home after an unsuccessful session of bike riding with Ryan, Grace and Graham were trapped when a swarm of Gathering coils attacked their train in search of Karl Wright, a fellow passenger. She, along with Graham, Ryan and Yasmin Khan, helped the Thirteenth Doctor battle both the coil and its controller, Tim Shaw.
While the Doctor was recovering from her recent regeneration, she slept on the sofa in Grace and Graham's home, with Grace and Ryan witnessing the residual regeneration energy swirling around the Doctor's body. Grace felt her wrist and realised that the Doctor had a double pulse. Later, Grace and Graham followed the Doctor's orders to pose as construction managers and evacuate the construction site Karl worked at, so the Doctor, Ryan and Yasmin could rescue him.
However, the gathering coils were still active, with Tim Shaw using them to damage the crane that Ryan and the others were on. Despite Graham's protests, Grace climbed up and destroyed the creature by electrocuting it with live cables. However, Grace was also electrocuted in the process and fell to the ground. Mortally wounded, she died in Graham's arms, after telling him to not be afraid without her. Graham later spoke of how Grace inspired him during their three-year marriage at her funeral. (TV: The Woman Who Fell to Earth)
Legacy
In response to his grief, Graham had several visions of Grace in the house where the couple had lived together with Ryan. He told the Doctor that he didn't want to stay at home, haunted by memories of all he had lost, and he instead wanted to travel with her. Graham's travels in the TARDIS helped him cope. (TV: Arachnids in the UK)
The Solitract took the form of Grace in order to try to convince Graham to stay in the Solitract universe, but Graham saw through the deception, as the Grace duplicate showed a lack of concern for Ryan when he was trapped in the anti-zone, which was something that Graham knew the real Grace would never do. (TV: It Takes You Away)