There are three (people) whose actions are not recorded by the Pen: a sleeping person till he awakes, a boy till he reaches puberty, and a person with an unsound mind till he regains his sanity

A person’s lack of eligibility is either due to sleep, which may cause him to fail to wake up to perform his duties, or because his young age is associated with legal incompetence, or because of insanity with which his mental functions are disturbed, as well as similar cases such as drunkenness. Whoever becomes unable to discern matters and perceive them properly is no longer legally qualified due to one of these three reasons. Allah Almighty, out of His justice, forbearance, and generosity, has absolved him of the blame for his transgression or shortcomings with regard to the right of Allah Almighty.
Not recording their sins against them does not contradict the establishment of some worldly rulings against them. For example, if an insane person kills, there is no retaliation or expiation due against him, and his paternal family members must pay blood money.
Puberty has three signs: the emission of semen, through a wet dream or otherwise; the growth of pubic hair; and reaching the age of fifteen. A woman has a fourth sign in addition: menstruation.
As-Subki said: A boy is a child. Someone else said: A child in his mother’s womb is called a fetus, and when he is born, he is a child. When he is weaned, he is a boy until he is seven. Then, he becomes an adolescent until he is ten; then a minor until he is fifteen. What is certain is that he is called a boy in all of these cases. This was said by As-Suyūti.