After 1928, children became the main subject-matter in the work of the prominent Czech painter, illustrator, and writer, Josef Čapek. At that time, his daughter Alenka was of school age, and it was for her that he wrote and in 1929 published The Adventures of Puss and Pup, illustrated with his own drawings, which remains widely popular at present. In the early 1930s, he also illustrated a lot of fairytales and short stories for children, among others the book Letňáskové by Pavel Sula, in which he sought a new dimension in the relationship between text and illustration. Instead of a descriptive approach, he chose a free illustration inspired only by the atmosphere of the story, based mainly on observing children’s games around his daughter. This led to the converging of motifs between his book illustrations and other independent artwork. The painting Boy in a Red Jumper depicting a small boy with a distinctive coloured jumper and a very unique triangular hat, which is also abundant in the book Letňáskové, likely draws inspiration from this. Josef Čapek was never interested in portraits; his images of children are often a personification of childhood itself rather than a depiction of a particular child. He saw the elementary basis of humanity in children, and his paintings seemed to be a medium for understanding children’s experiences and reality. In 1932, it was exhibited in the Municipal House, Prague, at the Umělecká beseda members’ exhibition. On the reverse, there is also a stamp of the 398th exhibition organised by Umělecká beseda in Prague in 1946, but this time it was a solo exhibition entitled The Work of Josef Čapek: Paintings – Drawings – Graphics – Theatre. Assessed during consultations by prof. J. Zemina and PhDr. K. Srp. Attached is the expertise by PhDr. P. Pečinková, CSc, the author of the upcoming inventory of the artist’s work.