This summary is not the rule. The rule text controls.
If someone wants a child to testify as a witness in a family court case, they can't just call the child to the stand. They must first ask the court for permission. The judge will decide whether the child should testify at all, and if so, how that testimony should happen.
The court has options here. A judge might decide the child shouldn't testify directly, or might set special rules for how the testimony is given, such as where the child sits or how questions are asked. The court can also appoint someone called a guardian ad litem to look out for the child's best interests before any testimony happens. This person's job is to make sure the process doesn't harm the child and that the child's needs are protected during the case.
This rule exists to protect kids from unnecessary stress or harm when they get pulled into a legal case, often one involving their own family. It gives the judge control over the situation so the child isn't put in a difficult position without careful thought first.