In 1940, full of love and the innocence of childhood, Kathy Gillis vowed to be an artist. It was a profession her mother, Doris, had once aspired to. Polio robbed Doris of the chance to fulfill that dream, as the virus later spread to Doris’s brain, making her unable to function. Gillis voiced her intention to be an artist to her grandmother, Gillis’s main caregiver. It was the first huge promise she made, and fulfilling that vow continues to motivate her to paint. In the intriguing virtual exhibition “Pure Heart: Kathy Gillis’s Oil Paintings,” Gillis recounts the experiences throughout her life that have shaped her—and her art. Gillis tells us how, as a schoolgirl, she enthusiastically copied all the illustrations in Victor Perard’s “How to Draw.” And she recounts how, in the 1960s, when her children were taking their afternoon naps, she would snatch pockets of time to complete a …