I have daughter she ihas convulsions even no fever...

is it possible that your daughter may have convulsions in the future ?
its all depends on daignosis first , if the previous convulsion were only one and happen in brief time and didnt happen again , then doctor doctor will do the tests , and if the patient doesnt have epilipsy signs and symptoms , then doctor will only prescribe the medication for short term , but if patient have epilipsy signs and confirmed by the diagnosis , then doctor will prescribe the medication for long term 
- we are not sure about your daughter diagnosis , but epilipsy patient have the potential of having a convulsion in the future 
should your daughter stop taking the medication ?
only the doctor will decide that , and usually doctor will prescribe anti- convulsion medication for 2 years period , and if the patient didnt have any more  convulsions , then doctor will stop it 
how can you prevent it ?
as we said , we dont know your daughter diagnosis , but the main advises are :
- consult patient doctor before stoping or taking any medication 
- avoid stress 
- avoid any triggers ( if there is specific and clear one such as noise or smoking or specific food and so on )