Diarrhea and vomiting suggest your daughter is probably suffering from Gastroenteritis. Gastroenteritis may be caused due to bacterial, viral or protozoal infection. Bacteria called Salmonella can be transmitted from guinea pigs to children and can cause diarrhea, fever, vomiting etc. However this needs to be confirmed by laboratory tests Treatment for this condition is antiemetic like ondansetaron for vomiting, ORS solution to prevent dehydration, paracetamol for fever, and antibiotics. Consult your doctor for further investigation and prescription of medicines.