Need advice about sick policy

[hockey mom]

My policy stipulates that children with coughs and colds may attend provided that there is no fever, nasal secretions are clear, coughs are not persistent and they can participate cheerfully in normal daycare activities. If yellow or green goop is pouring out of their nose or they are constantly hacking, they should be at home recuperating for the child's comfort and the health of the group. I added this clause after I had one child that often got colds so bad, green snot would literally hang from his nose to the floor when he sneezed and the parents continued to bring him. Clearly the child felt quite crappy and miserable, but the parents didn't want to be inconvenienced.