J.K.
Most cold medications are not recommended to children under 6 years of age (according to the FDA). The reason being is that they find them ineffective in treating the cold symptoms in children that young. However, I know if your child is not feeling well you want to help. I am aware of over the counter options such as dimetapp has a grape flavored bear sucker to get the medicine, many products now offer the dissovlable medication strips that you place on your child's tongue and it dissovles and flavored I think grape and cherry.
Once again the box will read for children under 6 years of age....consult your doctor. I have to state this b/c I am a pharmacist. However if your call your doctor office they will tell you how to dose the medication correctly according to weight, etc.
Hope it helps