In May 2018, Jonathan took Leigh-Anne Carr's son Kiegan off his oxygen to see if his health had improved. After witnessing her and ED consultant Ethan Hardy sharing a hug, he warned Ethan about the potential consequences of their relationship. Later, Jonathan treated Kiegan again when Leigh-Anne claimed that he was cyanotic. He concluded that Kiegan was perfectly healthy, prompting Leigh-Anne to ask for a second opinion from Ethan. (CAS: Episode 1085)
In July, following a stressful shift, Jonathan argued with his wife Cat and his son Finn about him returning home late. As Cat tried to repair Finn's car to take part in the county trials, she was sprayed with a flammable liquid and caught fire after the jump leads sparked. The ambulance team arrived and took them to the ED. There, Charlie comforted Jonathan as he had a panic attack, and he encouraged him to be there for his wife. In resus, Cat asked him if he was having an affair, and he firmly denied it. As her condition worsened, he told her about his futile fight to save a baby who died, and she believed him. In the relatives' room, Jonathan consoled Finn and promised to cut his hours to look after him and his mother. (CAS: Episode 1092)
Behind the scenes
Simon Shepherd initially portrayed Jonathan on Casualty for one episode in March 2017. He made two more appearances on the show the following year in June and August.