Grace O'Brien

Grace O'Brien was the paternal grandmother of Ryan Sinclair. She lived in Sheffield with her second husband, Graham O'Brien, whom she met during her work as a chemo nurse. (TV: The Woman Who Fell to Earth)

Grace was interested in the American Civil Rights Movement. 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". Graham recalled that she owned a t-shirt that said "the Spirit of Rosa," and believed that Grace would have been disappointed that Ryan couldn't recall Rosa Parks's role in the Montgomery Bus Boycott. Ryan remarked to Martin Luther King that Grace loved him, as well as jokingly saying that she would have started a riot in 1955 Montgomery. (TV: Rosa)

Grace would often attempt to teach Ryan how to cycle, which he struggled with because of his dyspraxia.

Whilst returning home after an unsuccessful session, 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)