Children

Characters who are children, or were children when they debuted in their respective stories, even if they went on to age into adulthood.

A child is a person under the legal age of majority. Someone below this age is also called a "minor". The concept varies by differences in law and culture. In the United States of America today, the legal age of majority is 18. In Japan today, the legal age of majority was reduced from 20 to 18 on April 1st, 2022.

Many incarnations of Leonardo, Donatello, Raphael, and Michelangelo are children—teenagers, specifically.