Research challenges the popular stage theory of grieving:
"Grieving is not a stage-like, sequential, orderly, predictable process across time. Bereaved people do not (and should not expect to) go through a set pattern of specific reactions. Grief can involve complex, fluctuating, emotional reactions (sometimes experienced as a ‘‘roller coaster’’). There are different patterns of ‘‘normal’’ (as well as complicated) ways of grieving. Patterns vary greatly in terms of specific reactions, time-related changes, and duration of acute grieving period. There are large individual/cultural differences in reactions to loss. There is no sound scientific basis for Kübler-Ross’s stages."
The research recommends that those teaching on grieving or offering support for those grieving should explore some of the other research and models. More information at this link: https://journals.sagepub.com/doi/pdf/10.1177/0030222817691870