My apology for the delayed response. Diarrhoea is usually self limiting, which means that it should resolve within the first 1-7 days. However if this is still an ongoing problem i would advise that you return to your doctor.
Keeping them hydrated and replacing lost electrolytes are very important as dehydration is one of the main complications of diarrhoea. Make a solution using 1 litre of boiling water with 8 tsp of sugar and a half teaspoon of salt. The kids should try to drink between 1/4 cup to a full cup (depending in the age of your kids) after every loose stool passed.
The simplest diet to follow would be the BRAT diet. This Bananas, Rice, Applesauce, and Toast