Seeing my mom had a baby in dream is a peculiar thing and If you see baby in dream, then meaning of the dream can be different than my mom had a baby. If your mother is pregnant, then you may see such dream. If you have seen any film like that, then your subconscious mind may think of it. If you see your mother in dream, then meaning also vary. However, if you are thinking that you had any sibling in real life or in subconscious mind, then you may see such peculiar dream. You do not need to think of the dream. It is not necessary that all dream has any specific meaning.