Suspect Parents are Lying

[gcj]

I would just tell them that since another child in your care has this, that you need them to resee a Dr to check him out and bring you a letter from the Dr stating what it is for the protection of that child and all the others.

[mom-in-alberta]

I would just tell them that since another child in your care has this, that you need them to resee a Dr to check him out and bring you a letter from the Dr stating what it is for the protection of that child and all the others.

Exactly this. And don't be "nicey-nicey" about it, either. I mean, you don't need to be a cow, but ensure that they understand you mean business!!
Impetigo is INSANELY contagious and needs to medication, to the best of my knowledge to get rid of it. As a nurse, the mom should really have seen this as an issue? I am surprised. So either they did, indeed, bring him all the while knowing. To this, I would say goodbye! But I don't suppose that you have any way of knowing for sure. Could be just REALLY irresponsible/ignorant parenting. Grrrrr.