Herbal Infusions with a little sweetening from maple syrup or honey is a great way to introduce both nutrients and gentle, effective medicine. Most are easy to prepare with 1 tsp dried/1tbsp fresh herbs per cup of hot water.
Lemon Balm (Melissa officinalis)
Good for general tummy aches, is relaxing and hot water extracts have antiviral properties.
Chamomile (Matricaria recutita)
Relaxes the whole body, good for gas or colic pains, can also help relieve non-infectious diarrhea and constipation.
Ginger (Zingiber officinalis)
Can help kids cough up any mucous that is sitting in their chests/lungs. Helps relieve nausea and motion sickness.

As a general rule, kids 3-5 years old can drink a ¼ cup and kids 6 to 10 years old can drink a half cup. By 10-12 years of age, the gastrointestinal tract is usually fully developed and therefore kids in pre-teens and adolescence can usually tolerate the adult dose of 1 cup.