Complex sentence: Chicago's Art Institute remained a loyal patron, of sorts, to its former student Irvine, often showing his recent work, and granting him a prestigious solo show in the 1916-1917 Christmas season.
Split into simpler sentences: Chicago's Art Institute was to remain a loyal patron, of sorts, to its student Irvine. In the early years of the Twentieth Century, the Art Insititute often showed Irvine's work, including at a prestigious solo show over the 1916-1917 Christmas season.