Brain children are ideas or concepts that are born out of the human mind. Their antonyms, on the other hand, include dullness, ignorance, and thoughtlessness. Dullness denotes a lack of creativity, while ignorance is a lack of knowledge or understanding. Similarly, thoughtlessness implies a lack of consideration or care in the ideas or concepts presented. Brain children represent the intellectual capacity of a person, while their antonyms represent the opposite end of the spectrum, where a person lacks mental acuity or the ability to produce novel and worthwhile ideas. In conclusion, by finding antonyms for the term brain children, we can better understand and appreciate the importance of creative and innovative thinking.