Lofty and Dom's relationship is tested by the arrival of Lofty's grandmother, Sheilagh Chiltern. Wanda Ventham was cast as Sheilagh and is introduced in January 2018. Sheilagh is admitted to the AAU following a fall in the garden; when Lofty becomes upset, Dom supports him. Lofty then starts to question his relationship with Dom. Sheilagh's deteriorating health means that she cannot be released from hospital. Mead explained that Lofty is concerned about his grandmother's safety and wants to make her "comfortable and safe". Lofty considers moving Sheilagh into a care home, but she is adamant that she does not want that. Dom suggests that Lofty and Sheilagh move into his flat with him. Mead told Victoria Wilson of What's on TV that Lofty "freaks out a bit" over Dom's proposal, but understands that it is "a kind gesture". Lofty tells Dom that he is not comfortable with living with Dom and Sheilagh, which makes Dom question whether Lofty has feelings for him.
