The family lifecycle (FLC) idea has been particularly threatened. The FLC traces the development of a person’s life along a path from young and single, to married with no children, married with young children, married couples with older children, older married couples with no children at home, empty nesters still in employment, retired empty nester couples, to sole survivor working or not working. Life for many, if not most people, does not follow this path. It fails to take account of the many and varied life choices that people make: some people never marry, others marry late, there are also childless couples, gay and lesbian partnerships, extended families, single-parent households and divorced couples.
The word "nester" seems odd to me. I don't know if it is person or place (used with empty). Witionary and Urban Dictionary's definitions also do not seem to fit in this context. Then, what is it, especially in US English as I think the text is in American English?