It is best to involve a family lawyer in your Intervention Order matter as soon as possible.
The lawyer can give you advice as to whether you have grounds for an Intervention Order and help you to prepare your application.
Whilst some Courts may offer a free 'duty lawyer' service for the first Court hearing, some Courts do not offer this service, and it may therefore be preferrable to engage a private family lawyer to represent you.
If the matter does not resolve at the first Court hearing, then it will likely be necessary to ensure that you have a family lawyer represent you at the subsequent hearings.