What could cause a couple to have 2 kids with cerebral palsy?

Bad luck: Some women have trouble during pregnancy. Even without any outward signs the woman may carry an infection or carry a risk for thrombosis that can damage the fetus and result in cerebral palsy. Detailed discussions should occur with her doctor.

Preemies?: Although many answers are possible children who are born prematurely or with low birth weight are statistically more likely to have cp. This does not directly answer the question, but any condition which results in early birth could theoretically increase one person's risk of having a child affected by cp.

CP is a group of : chronic childhood motor impairments. A wide range of genetic etiologies cause abnormal fetal brain development as early as 3-9 weeks after conception. A pediatric neurologist would compare the siblings' clinical findings, abnormalities on MRI of the brain & EEG, growth & developmental trajectories & results of their Chromosomal Microarrays & DNA Probes for Fragile X, then refer to a geneticist.