Genius is a very rare thing, and it often takes years of education, study and work to attain it. But genius can begin to show itself at a very young age, resulting in Teen Geniuses and Child Prodigies. But what happens if it shows up even sooner than that? The result is the Brainy Baby. Some cases of this trope are actually smart adults or teenagers who've been subjected to reverse aging. Others are some variety of immortal and age much slower physically than mentally. Examples of Brainy Baby include: