I guess if the grandparent is relatively trustworthy (not always a "given") so that the grandparent's portion wouldn't be suddenly "interrupted" for petty reasons a child may not really "get"; you don't suspect that the grandparent would withhold the allowance in a situation that you'd disagree with, and they are overall on the same page about the purpose of the allowance and how it is managed... I guess not.
I'm not sure you've thought about this, but we increased our son's allowance each year. We started at 5yo and he turns 9yo soon. Wondering if you do this, will your LO expect the grandparent to do it as well...?
Just things to think about... kwim?
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