Empty nest syndrome?

[Kathleen DiMaggio]

Is it my misinterpretation, or do gerbil couples get depressed when their
youngsters leave home.  My original breeding pair, who share a particularly
strong bond, always seem tired and disinterested for a little while after the
last two youngsters are adopted out.  If they already have newborns, however,
they don't seem to mind at all.  Do others see this "empty nest syndrome" in
their gerbils.