Javier Sobrino (Asturias, Spain, 1960) is a primary school teacher, award-winning writer and researcher on children's literature and reading promotion. He has written for the Santander children's magazine "Peonza" for 28 years. He has planted many trees and published around twenty books, predominantly illustrated. He likes collecting spinning tops, lighthouses, and friends. He would like to finish the Tower of Babel, sail the Amazon, discover the secrets of Samarkand, walk the streets of Macondo, and travel through Utopia.

Carolina Luzón, Born in Barcelona in 1972, holds a doctorate in Fine Arts from the University of Seville and a degree in Audiovisual Communication from the University of Granada.  After a long and flourishing pictorial career, full of exhibitions (solo and group exhibitions in Spain, Italy, France, and the United States) and prizes for painting and drawing (including the Gregorio Prieto First Prize, the First Prize of the City of Tomelloso and the First Prize of the Province of Guadalajara), she moved to Italy in 2011, where she has focused her career on illustration and works as a drawing teacher in Florence. She has published more than a dozen books. 

The Footprint - The brilliant work of the artist and, specifically, the realism with which Luzón brings this story to life forces us to experience the protagonist's emotions in every stroke. "Throughout the book, a striking contrast emerges an animal world with human feelings."The compositions and techniques with which the artist plays to recreate the various scenarios and breathe life into the protagonist's emotions overwhelm the reader to the point where it is impossible not to empathize with him. Images and verses that envelop us in an atmosphere as turbulent as friendship can be a difficult beginning, with an initial rejection of the different, what we call "strange," which quickly finds that gift of life called friendship, the one that allows us to face and even forget all the adversities that cross our path. A strong and intense friendship that carries us along on a river of fun and well-being and that both Sobrino and Luzón manage to make us feel between the pages of this beautiful album. Companionship can be one of the most beautiful experiences to be discovered in childhood, but it can also be one of the most painful when it breaks down. That's why this story isn't just about how good it is to have a great friend. Sometimes things go wrong; paths diverge, and, without expecting it, lives that were once one become separated forever. Dealing with the grief you experience, especially for a child, is not easy. This is why this beautiful book gives us a powerful message of hope and illusion:"That those who were here may have left an indelible mark, but they also leave a space that can be filled by others who are ready to make us immensely happy.". Because in childhood, during emotional turmoil, friendship can be a wonderful experience or the most significant lesson. La huella - A lo largo de la infancia, los niños pueden sentirse muy afectados y tremendamente tristes ante la ruptura de una amistad o ante las circunstancias que lo obliguen a separarse de su mejor amigo.Este hermoso álbum ilustrado representa un extraordinario recurso para abordar el duelo por separación, contribuyendo al aprendizaje de una correcta gestión emocional. El brillante trabajo de la artista, Carolina Luzón y, concretamente, el realismo con el que da vida a los personajes de este libro nos permite vivir las emociones de su protagonista en cada trazo y nos lleva a empatizar con él Javier Sobrino nos recuerda la maravillosa complicidad que se genera con la amistad y cuán felices puede llegar a hacernos. Pero también nos advierte de la posibilidad de su ruptura o término por distanciamiento. Por eso nos deja este precioso y emotivo libro donde nos regala un poderoso mensaje para enfrentar ese duelo con ilusión y esperanza:"Puede que alguien nos haya dejado una huella con su partida, pero también deja la oportunidad de que otros lleguen a nuestras vidas para hacernos felices".