Child helplines play a crucial role in delivering expert assistance to young clients facing challenges and seeking support. While counselling is instrumental in enhancing children’s mental well-being, the limited number of experienced counsellors is inadequate given the substantial workload. At this point, effective training to volunteer counsellors becomes essential. This thesis aims to expand upon a Belief-Desire-Intention (BDI) based chatbot, the simulated child, with the specific objective of enhancing volunteer training at child helpline organizations through the integration of emotional capabilities. Through the collaboration with professionals from a Dutch child helpline, the Kindertelefoon, we identified the predominant emotion of frustration along with its underlying triggers. Armed with this insight, we proposed an Emotion-BDI model capable of dynamically adjusting the chatbot’s displayed emotion in response to its environment. The evaluation of a prototype constructed based on this model supported our hypotheses that a chatbot equipped to express frustration possesses greater believability and emotional presence compared to the original version. Moreover, it also indicated heightened user enjoyability, engagement, and perceived usefulness. Within this thesis, we highlighted the enhanced feasibility of the simulated child brought about by our proposed Emotion-BDI model.