In healthcare areas, social robots have demonstrated positive effects on adherence to procedures and cognitive skills development. This paper explores the effects of a social robot during an introductory phase in Cerebral Palsy rehabilitation. A human-Robot interface was deployed to promote the interaction with the children through 10 activities, including a presentation stage and imitation games. Besides, the interface aims to ease using the social robot to the therapist and allow them to control the robot's non-verbal and verbal gestures. The interaction was measured through joint attention, attitudes, and follow-up instructions. A total of 10 children participate in this study. The results suggest that 80% of the participants have a joint attention rate of 70%, and they accomplish highly the requests given by the robot. These preliminary findings show a positive effect of the robot on the children.