Stand-on Ride-on Power Mobility Devices for Children With Cerebral Palsy

The goal of this interventional study is to learn about the biomechanical factors underlying the beneficial changes in children with cerebral palsy after using individually-adapted stand-on ride-on power mobility devices (PMD). The main questions we aim to answer are: * How does the use of stand-on PMDs affect static balance in children with cerebral palsy? * How does the use of stand-on PMDs affect dynamic balance and mobility function in children with cerebral palsy? Children ages 4-6 years old with cerebral palsy (GMFCS levels II and III) will: * Use individually-adapted stand-on PMDs for three months. * Undergo tests to measure static balance, dynamic balance, and mobility function before and after the intervention. * Receive a full biomechanical assessment (kinematics, kinetics, muscle activity, gait spatiotemporal characteristics). Researchers will compare pre-intervention and post-intervention measurements to quantify improvements in balance, muscle activation, and mobility.