|I am going to respectfully disagree with the above post. Bipolar disorder is diagnosed in children. This is usually in school age children but has been diagnosed in preschool age children. I do agree with Marianne's post in that diagnosing a baby is probably not going to happen. Furthermore, treatment includes medications that have not been used in the pediatric population in children that young. There are not any clear cut symptoms in a baby that you can refer to that may indicate bipolar disorder.
As for your baby having bipolar disorder, the chance is there. It is greater if both sides of the family have history of bipolar disorder.
Try to relax. Enjoy your baby. You can not change the genetic code and prevent any disorders. Try not to worry about this too much. Many people that have bipolar disorder have children that never develop the disorder.