Each child has four study assessments during their ~6 months in the study. The first assessment is done before starting the Lokomat or physiotherapy phase. The second happens after the first intervention has finished. The child then has a 6-week break period. The third assessment is done at the end of this break, and the fourth occurs after the second intervention. The PT assessor who does these assessments will not be the same as the PT who gives the intervention. The assessor is blinded to the child's intervention phase and previous assessment results. The primary outcome measures are the Gross Motor Function Measure and 6 minute walk test. Secondary measures evaluate gait, functional abilities, participation, health related quality of life and individualized goals.