Mònica Peitx is a Barcelona-based paediatrician specialising in endocrinology and nutrition. She wrote her first book, El cuento de Max' ('Max's Story') for overweight and obese children, in 2008. She followed this with 'El Cuento de Aina' ('Aina's Story') about diabetes, and 'El cuento de Quim' ('Quim's Story') about children's size and body shape. Cristina Losantos has a degree in fine art from the Universidad de Barcelona. She has been a professional illustrator since 1985 and works for numerous Spanish and European publishers. She is a regular contributor to magazines and papers including Avui, Cavall Fort and El Tatano. She has won various prizes including the second Premio Nacional de Ilustración in 1998.