I consider reciprocation in a healthy relationship to be a voluntary give/give situation based on judgment, need, and care for one another; not a take/take parasitic one. s/family unit/family relationship/ in my prior post

Taking care of children and the elderly are of course one-sided cases, but when two generations are both adults (pre-elderly parents, adult children), and among siblings, a healthy relationship and taking care of each other goes a long way in times of struggle on otherwise equal footing.