You are thinking of Vincent Van Gogh, whose brother Theo supported him during his long, tumultuous days as a French painter. Van Gogh’s painting, impressionistic and to the untrained eye chaotic, had no patrons in the Parisian community, nor in the French countryside of Arles. Rather than simply send him money (which Vincent spent on more paint), Theo would demand paintings in return for his support. This was an incentive for Vincent to continue his efforts, despite harsh criticism from his colleagues, such as Paul Gaugin. Occasionally he would paint local figures and their children, possibly in payment for his patronage. Vincent’s letters of gratitude and love are gathered into the biographical Dear Theo from which we get a great deal of Van Gogh’s biographical information. There is some controversy about Vincent’s final acts, but it is clear that Theo supported him, financially and emotionally, all his life.
He was Dutch but moved to Paris in 1886 and became an Impressionist.