On February 19, 2016, at the age of 89, Harper Lee, the author of the famous autobiographical novel To Kill a Mockingbird, which would go on to win the award Pulitzer Prize, died. Made into a film two years later with the same degree scroll, it won three Oscars.

 The novel describes an episode of racial segregation in the USA: the honest lawyer and family man, Atticus Finch, defends an African-American man, Tom Robinson, falsely accused of the rape of a white woman, in the context of the racist South.

Several children play a major role in the story. The narrator is six-year-old Scout Finch, Atticus' daughter, who lives with her brother Jem. Both are friends with another child, Dill. The three secretly witness Tom's trial from the balcony reserved for blacks and are shocked that the jury judges him guilty, despite his obvious innocence.

The main message of the novel is the problem of the premature loss of innocence, already hinted at in his degree scroll. Atticus warns his sons that, although they can shoot blue jays with his shotgun, they should not shoot nightingales, because "it is a sin to kill a nightingale."

Harper Lee uses the figure of the nightingale to symbolize innocence. A neighbor makes it clear to the girl Scout that nightingales cause no harm to anyone, and that they only do one thing and that is to sing their hearts out to our delight.

The innocence of children is the absence of malice. They lack the experience of evil. Some adults mistakenly see it as a status of ignorance and naivety, which must be corrected as soon as possible; they do not change their minds even in the face of the fact that children are reluctant to abandon the first beliefs that nestle in their fantasy.

It is said that a five year old boy was reproached by a teenager of the same age high school for his belief in the Three Wise Men. The boy, undeterred, replied: "Well, my mother does believe, and she is 40 years old".

Ignorance must be overcome, while innocence must be protected. J. B. Torelló provides a good argument: "The play, laughter and singing of children are not only symbols of spontaneous vitality, forms of expression of their incipient intelligence and personality, but a particularly exemplary realization of human existence that corresponds much more to the Creator's project than our seriousness and our activity".

A child's innocence is not incompatible with small pranks. The humorist Forges describes the status of a mother with her child in the pediatric enquiry : the child jumps continuously and in one of them steps on the doctor, which decisively influences the change of treatment: "we are going to take away the vitamins and give him every six hours a couple of well-delivered cakes".

Juan Ramón Jiménez evoked his own childhood using the symbol of a bird he heard singing in the garden. That garden is the mirror of an innocent and happy childhood:

"Enclosed garden, where a bird sang/through the greenery tinged with melodious golds/soft and fresh breeze, in which came to me/the distant music of the place of bulls."

He also alluded to the innocence linked to fantasy in Platero y yo:

 "What a charm this of childhood imaginations, Platero, which I don't know if you have or have had! Everything comes and goes in delightful bartering; one looks at everything and sees it only as a momentary image of fantasy".

 The Canadian researcher Catherine L'Ecuyer has recently vindicated the importance of innocence, because "we are skipping a necessary stage for the development staff . Minors are not unfinished adults, but children with their own maturity. At that time of life, play, imagination and creativity must be encouraged". He also warned of the risks of shortening childhood, because if it is not lived at the right time, it is lived later, and then infantilism arises in adults.

Skipping the age of innocence is equivalent to silencing a nightingale. To achieve this it is not necessary to kill it; it is enough to lock it in a cage. In the case of the child, this is achieved by throwing him recklessly into the outside world before his time. For example, by allowing him to watch television alone, to enter the Internet without parental control and to entertain himself with video games that incite sex and violence.

The child, if he does not lose his innocence in advance, possesses a set of values that make him model for the life of childhood or spiritual infancy at any age. For example: simplicity, humility, sincerity, trust, audacity, gratitude, perseverance, filial sense and withdrawal.