Franco Villavicencio (R), four years old, interacts with his family, at home in the town of Moreno, in the province of Buenos Aires, Argentina, on May 13, 2015. Franco suffers progeria (or premature aging). Children with this disease look healthy at birth, but during the first year of life begin to show characteristics of the pathology as lower growth, hair loss, skin aging etc.. (Xinhua/Martin Zabala)

Franco Villavicencio (R), four years old, plays with his cousin, at home in the town of Moreno, in the province of Buenos Aires, Argentina, on May 13, 2015. Franco suffers progeria (or premature aging). Children with this disease look healthy at birth, but during the first year of life begin to show characteristics of the pathology as lower growth, hair loss, skin aging etc.. (Xinhua/Martin Zabala)

Franco Villavicencio, four years old, watches TV cartoons at home in the town of Moreno, in the province of Buenos Aires, Argentina, on May 13, 2015. Franco suffers progeria (or premature aging). Children with this disease look healthy at birth, but during the first year of life begin to show characteristics of the pathology as lower growth, hair loss, skin aging etc.. (Xinhua/Martin Zabala)

Franco Villavicencio (Front), four years old, rests in his mother's arms, at home in the town of Moreno, in the province of Buenos Aires, Argentina, on May 13, 2015. Franco suffers progeria (or premature aging). Children with this disease look healthy at birth, but during the first year of life begin to show characteristics of the pathology as lower growth, hair loss, skin aging etc.. (Xinhua/Martin Zabala)