"My brother does nothing"

The sums. Nearly everyone caring for a parent has a sibling in the sums, and the sums are always the same. You do the most. It isn't fair. And there's a particular flavour of guilt that goes with it, which is guilt about the resentment.

Jennifer Willyard and colleagues interviewed 25 family carers in 2008 about how caring for a parent was divided among siblings, and the first finding was that it mostly wasn't divided at all. There was little negotiation. One person, usually a daughter, ended up doing it, and the arrangement arrived without anyone deciding it. The carers then made sense of the imbalance in three ways. Some saw caring as something they were personally suited to. Some excused the sibling by defining them as somehow outside the family's obligations. And some, who believed in family duty and couldn't excuse the sibling that way, went back and forth in the telling, unable to settle the story.

A separate study by Berit Ingersoll-Dayton and colleagues in 2003 used focus groups of 40 people to look at how siblings try to fix the imbalance once they've noticed it. Two routes. Ask the sibling to change. Or change how you think about it. And the finding that matters here is that both routes could make things better and both could make things worse, producing more perceived unfairness and more distress, not less.

So the sums aren't the reason for the arrangement. The arrangement came first, by default, and the sums came after, as a way of living with it. And here's the link to guilt. If the sums say you do the most, the sums also say, in the same breath, that the most isn't enough, because you're still measuring it. The tally never comes out in your favour, even when it does. My interpretation is that a person who keeps the sums has usually never asked the sibling for anything specific, which is chapter 9, and has never decided what their own share is, which is chapter 20. The sums are what you keep when neither decision has been made.