Cerebral palsy (CP) is a broad term used to describe a group of chronic palsies -- disorders that impair control of movement due to damage to the developing brain.CP usually develops by age 2 or 3 and is a nonprogressive brain disorder, meaning the brain damage does not continue to worsen throughout life.t is present at birth, although it may not be detected for months. It is responsible for CP in about 70% of the children who have it. An additional 20% are diagnosed with congenital cerebral palsy due to a brain injury during the birthing process. In most cases, the cause of congenital cerebral palsy is unknown.