Many have problems that require on going therapy and devices such as braces or a wheelchair which leads to them not being able to do things others children can do so they end up not interacting. Other areas of development which will suffer are - difficulty feeding/sucking, poor hearing and eyesight, bladder and bowl movement control. (3.3 - Amena, Stella and Sam)
Here The Cerebral Palsy Site has put together a visual representation of facts about Cerebral Palsy and also UK statistics, from the types of Cerebral Palsy, the causes and ranges of treatment available.
Six Types of Adaptive Equipment for Children with Cerebral Palsy | Healdove