I have a particular soft spot for Ibejis (or ere ibeji), sculptures of deceased twins made by the Yoruba people of Nigeria. The Yoruba have one of the world's highest natural prevalences of twinning (c.50 twin sets per 1000 births, compared to c. 11.1 globally), and many twins traditionally died in infancy. The coping mechanism the Yoruba have put in place to deal with this is remarkable. 

Twins are believed to be under the protection of an Orisha (spirit) named Shango, and in order to appease him and to keep a connection with the dead twin, the parents would visit a Babalawo (priest) who would commission a figure of the dead twin/s to be carved in the likeness of how they would have appeared as an adult. Only the sex is accurate to the deceased child, and the carver can take as many liberties as he likes with the appearance of the carving. It is then often dressed in flamboyant clothes, with cowrie shells, beads and coins, and carried about like a real child (tucked into the clothing) or placed on a household shrine. They are even 'fed' with metaphorical or real food, and many early figures' mouths are worn away from all the dinners they received from their families.

Ibeji are enormously variable, and entire volumes exist on how to nail down the origin of your ibeji to a couple of miles. In general terms they are short, squat figures about 6-12 inches (15-30cm) tall, with disproportionately large heads and complex coiffures. Their sex characteristics are usually well marked, and their legs are very short. They usually have some adornment, typically beads around the neck, waist and ankles/wrists. The figures are often shiny and featureless from generations of handling, and it is hard not to be moved at the thought of those long-dead hands caressing the figure and missing the child that it represented. 

I absolutely love Ibeji and the story behind them, and feel so sorry for them - imagine selling your child? - that I buy them and take them home to meet the others. Visitors to my house are often somewhat taken aback as they cover most of the shelves that are not filled with books.