Objectives: The aim of this article is to conceptualise the phenomenon of therapy-related parental stress in parents of children with a physical disability. Methods: Three models related to parental stress were reviewed, i.e., general parental stress, burden of caregiving in parents of children with physical disabilities, and experiences of these parents with their child's therapy. Findings: The proposed definition of therapy-related parental stress is "the subjective stress and subsequent changes of functioning and health experienced by a parent of a child with a physical disability in response to paramedical therapies (i.e., physical, occupational, and/or speech and language therapy)". A theoretical model is proposed to describe the process of therapy-related parental stress. Available questionnaires will most likely not be valid and responsive to capture the (changes in) stress parents experience related to therapy their child receives. This article provides a first definition of therapy-related parental stress and a theoretical model to visualise the processes with regard to this topic. Empirical testing of the presented components and their coherence is needed to confirm or improve the model. A questionnaire that specifically measures the concept of therapy-related parental stress is needed, along with evaluating therapy-related parental stress in clinical practice and research. It is imperative to recognise paramedical therapies (i.e., physical, occupational, and speech and language therapy) as a potential stressor for parents of children with a physical disability, both in paediatric rehabilitation practice and research. Conclusions: A definition and theoretical model of therapy-related parental stress is proposed and the need for measures to evaluate this phenomenon is argued. The authors provide a starting point for the evidence base of the concept of therapy-related parental stress.