V.W.
Be careful what you allow her to consume. Dairy is difficult to digest. Monitor her for signs of dehydration. Keep the fluids flowing, but the less sugar the better (in other words, juice might not be a good choice, but watered down it might be ok; plain water; oral rehydration solutions like pedialyte or something; or breastfeed if that is what you normally do).
Disinfect all her toys. It is not uncommon for toddlers to have a bout of rotovirus (which can include diarrhea). Most important thing is to be aware of the signs of dehydration. At the first signs, call the doctor and have her seen ASAP.