A tip for cold season...
Set up a cool mist humidifier in your child's bedroom. Make a solution of the following in a small bowl:
1. 2-4 drops of peppermint essential oil
2. 2-4 drops of eucalyptus essential oil
3. 2-4 drops of winter green essential oil
Take a cotton ball and dunk it into the solution. Tape the cotton ball near the tip of the humidifier. The refreshing smell will instantly clear your sinuses.