Antique Scottish oil painting portrait study of a domestic family scene

Antique Scottish oil painting portrait study of a domestic family scene. Scottish School, circa 1860-90. Unsigned, artist unknown. Oil on canvas, laid on board. Gilt frame (more modern). Depicts a domestic interior scene - man playing a Jews harp with girl in straw hat and boy in white choirboys gown, attended by their dog. Size of frame: 17 x 14 inches; Size of portrait: 15 x 12.5 inches; Size of front portrait aperture: 15 x 12 inches. Weight: 1.1 kg (allow 4 kg volumetric weight once packed). Condition commensurate with age - various superficial marks & scratches and some knocks to and pieces missing from gilt frame but all part of its charm and character.