... are not just emotional, but biological. It shortens a child's telomeres. While death has the biggest impact, divorce or incarceration have similar effects. Shortened telomeres correlate with shortened lifespan and worsened health. Now consider that in light of policies from prison to foster care. Losing a parent is the worst thing that can happen to a child. If they are not literally in immediate risk of death, everything else does less damage. That sucks, but it should be used to find other ways of solving family and social problems that do not butcher children's lifespan and health at a cellular level.
No mention was made of mothers. Likely the effects parallel those of father loss. I would not be surprised if they are worse.