Mental disorder during birth

This could be caused by genetics, by smoking cigarettes during pregnancy, drinking alcohol or doing drugs during pregnancy, or pregnancy complications, like lack of air supply to the baby....

Isabella gave a good answer. There are questions we just don't have a good answer for and we live and wonder why. God isn't mad at you. I will assure you of that, nor is He mad at your parents. Sometimes people think so. God loves us and is saddened when any of us are so affected. The natural order is carried out as it was created to do. Many genetic defects causes abnormalities everyday. We human have no answers. Why do babies have such diseases or abnormalities? I wish I knew. My only answer is wait it out uhtil we can ask the Creator behind this great world why some things had to be. I believe God cares for you and loves you as much as any one else so don't think children or adults with mental disabilities are any less loved or valued than other persons. Such attitudes are purely human.