She keeps telling me what is the big deal. I can't put my finger on it, but I do think it is a big deal for some reason. Or more correctly, you and your spouse are the only one s who should be making the final judgment on piercing your daughters ears. Your question about when is a value-judgment. There is no one right answer and every family needs to make up their own rules about this.
Some cultures pierce their daughter s ears at birth and others wait much later.
What is occurring here is what counselor s call a triangulation. If he or she cannot, you will have to draw the line. Tell your daughter when she can pierce her ears. The tough part is to stand your ground. If you do, eventually she will stop trying to control this issue and your daughter will give up going to grandma because she will know it won t work anyway.