The rules governing civil claims brought by or against children is governed by Civil Procedure Rule (CPR) 21 and its Practice Direction (PD). Under UK law we no longer refer to a minor these days and a child means a person under the age of 18 (CPR 21.1(2)).
If a claim is to be brought it is usually brought on behalf of a litigation friend. No person under the age of 18 can bring a claim until the child has a litigation friend. It follows that a court must approve any settlement and it will also direct how any money recovered may be dealt with.