This paper presents an experimental assessment of the children's receptivity to the human-like conversational robot MARKO. It reports on a production of a corpus that is composed of recordings of interaction between children, with cerebral palsy and similar movement disorders, and MARKO, in realistic therapeutic settings. Twenty-nine children participated in this study: 17 of them were recruited from among patients with cerebral palsy and similar movement disorders, and 12 healthy. Approximately 222 minutes of session time was recorded. All dialogues were transcribed, and nonverbal acts were annotated. A control group of 15 children (14 with cerebral palsy, one with spina bifida) was also included. The evaluation of the corpus showed that the positive effects go beyond social triggeringthe children not only positively responded to MARKO, but also experienced increased motivation and engagement in therapy.