The artists' nephew.
Anna, Dof and Coen got another brother in 1916. When he was 7 years old he got piano lessons, and from that moment on he played as much as possible on every piano he saw. Maybe that's why he had a special camaraderie with his uncle Coen. When he was older, he often stayed at the studio. Coen painted him twice more: in 1936 and 1938. He died of tuberculosis in 1942.
[http://stichtingcoenvanoven.nl/werken/jules-met-krullebol-1919/]