If you have no one at your house right now with the chicken pox then what makes this mom think her child got it at daycare - the incubation period is about 10 days and it will be from someone they were around that had a cold but no spots yet. Time to email the mom an info sheet on the disease.

Also chicken pox is no longer excluded from school or city run daycares because of the contagiousness although most invoke their no open sores rule to have the child stay home for a few days till scabbed over.