I am the mother of two young children, and extremely grateful to my own parents for looking after them for a few hours now and then. My problem is that they stuff the kids with chocolates, crisps and ice cream. This is not good for the children, their behaviour and my own efforts to feed them something nutritious. Why do the grandparents have such a different philosophy, and can I do anything to change their thinking?
The symptoms are familiar, but you have misdiagnosed the cause. Your parents do not have a different philosophy; they have different incentives. As you surmise, the costs of the junk-food strategy are mostly long-term: the children become fat, their teeth rot and they refuse to eat more wholesome fare.
In contrast, the benefits – delighted smiles, grateful kisses, compliant silence – are all short-term. Their strategy is perfectly rational for temporary carers.
Rather than reasoning with your parents, you must change their incentives. Unfortunately, this is not easy. You could try to bribe your parents, but threats will be useless because they are doing you a favour.
Perhaps your best bet is to try to arrange for longer bouts of childcare. Your parents will have a fresh perspective on the merits of carrots after trying to put a three-year-old to bed in the midst of a sugar high.
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