There is a general principle if someone is applying for an Order against another person, that person should be given notice and an opportunity to be heard. However, on an emergency application the Court has the power to make any Order without notice of the proceedings to any other party. To justify the use of this procedure the facts must be sufficiently strong to compel the Court to act without notice to protect the interests of the child.
There is a general duty on an emergency application to put all relevant information before the Court. This means you have to tell the Court of everything that is relevant, even if it may undermine your case.
The Court will always consider whether short notice may be more appropriate, in which case the Court can shorten the time for service on any other party. Where an emergency Order is made there will normally be a further hearing within 7 days to consider the issues further.