 The custom is based upon a belief that the spirits of the dead finally join the world of the ancestors after the body's complete decomposition and appropriate ceremonies, which may take many years.In Madagascar, this became a regular ritual usually once every seven years, and the custom brings together extended families in celebrations of kinship, sometimes even those with troubled relations.The practice of Famadihana is on the decline due to the expense of silk shrouds and belief by some Malagasy that the practice is outdated.