Belgium: Memling painting

Belgium issued this stamp (Scott 1560) as part of a set of two in 1994. This one features a detail from a painting by Hans Memling. The detail shows a woman holding an infant, a second woman on the left, and a musician playing a portatif in the background. It's not quite clear if the musician is indeed holding the instrument or if it rests on a table of some type. But it does meet the design features typical of portatifs: short compass, single set of pipes. The winding mechanism is not shown. I am not familiar with this painting, so I would be happy to hear information about the persons in the painting and any other details related to it. The other stamp in the small set of two features the Belgian composer Guillaume Lekeu (1870-1894). He died at a tragically young age of typhoid fever. Most of his pieces were for piano and strings, along with a dozen orchestral works.