Ryan Sinclair’s father
Sharon D Clarke
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. 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 Doctor battle both the coil and its controller, Tzim-Sha.
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 Tzim-Sha 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.. (The Woman Who Fell to Earth)
Graham had several hallucinations of Grace in his house where he lived with her. He told the Doctor that he didn’t want to stay at home as it reminded him of Grace and he instead wanted to travel with her to stop thinking about Grace’s death. (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. The Solitract, when talking with the Doctor in the form of a frog used Grace’s voice. Afterwards, Ryan comforted Graham, telling him that he thought about Grace all of the time too and accepting Graham as his grandfather for the first time. ()