If my house smells like poo, and yes sometimes it does, I do notice it. I'm sure you would too especially when you are coming in after being outside with the kiddies. Maybe she is just someone with a very keen sense of smell. When the weather permits, I am always airing out the daycare area. I prefer not to use spray scents or any other smell cover up as they bother me. In the winter, I keep the furnace fan going all the time (using the same energy as a low wattage light bulb) which helps with all odours. Anyway, I wouldn't worry about it, it is just part of the business.