I think a phone call 15-30 minutes prior to drop off with a question about whether a child is well enough to come to daycare is perfectly acceptable. There are times when a child may not seem to sick to come to daycare from a parents perspective so they are calling to get some reassurance of what the provider would like them to do. I don't see any problem with that. Rather that than dropping off a sick child or having to turn them away at my door when the phone call could have prevented dragging the child out. I have an extensive sick policy which goes into great detail but it is never going to be exhausted.....I encourage all my parents if they are ever unsure to call ahead.