As soon as practicable after an action to declare the existence or nonexistence of a father-child relationship has been brought, and unless judgment by default has been entered, an informal hearing shall be held. The court may order that the hearing be held before a master. The public shall be barred from the hearing. A record of the proceeding or any portion of the proceeding shall be kept if any party requests or the court so orders. The rules of evidence shall not apply.