I'm no art historian and I wonder who first had the idea of portraying disability with sympathy instead of ridicule or judgement. Was it Henri de Toulouse-Lautrec? Possibly it wasn't but he did paint with sympathy towards at least one of his muses: Jane Avril.
Avril was a Moulin Rouge dancer with a nervous disorder, diagnosed as St Vitus' Dance. She'd also survived an abusive childhood and some time in a mental hospital. Toulouse-Lautrece painted
a series of posters featuring her. He himself had 'crippled' legs from riding accidents in childhood and I wonder whether that affected his view of this exotic dancer.