Post-mortem photography
Post-Mortem photography by current standards was a curious practice, but was fairly common up into the late 19th century and was even practiced up into the early 20th century. The fact that early death — especially the early death of a child — was much more commonplace, and that photography was still somewhat of a novelty even in the later part of the 19th century, gave a societal acceptance to the practice of photographing the dead; often with some of the living family members included in the portrait.
This practice may have been somewhat more common in Europe, but was widely practiced in the USA as well.
Variations on this practice included photographing a family portrait with a “shrine” to the dead family member included in the pose or posing next to the grave of the departed. Items of the departed member, such as photographs, toys and flowers might all be included in the composition.