Legal Question in Wills and Trusts in Pennsylvania

Do not understand the question. I am aware of no criteria other than relevancy (assuming the witness is not testifying in some expert capacity; in that case, the witness would need to have whatever qualifications or life experience which would qualify him or her to opine on the area of expertise).

Why don't you ask what you really want to know? I assume you are wanting to speak. Why? What do you propose to say? Are you going to help the ward (the person for whom the guardianship is being established?) Or are you going to help the person who is trying to get guardianship? Or do you have negative information about the person seeking to establish guardianship which would make the proposed guardian unfit? Is this a guardianship over finances/property or a guardianship over the person (i.e. over money or assets or to make healthcare and other daily living choices) for the person? If you are there to support the ward, then talk to the court appointed guardian about speaking. If you want to help the person seeking guardianship, then talk to him or her or their lawyer about speaking. If you do not think that the person seeking to obtain guardianship is fit, you would still want to talk to the guardian. You say you are an "interested" person. What does this mean? In plain english - what is your relationship to any of the parties and why do you have a dog in this fight? Do not answer me. You need to think about these issues for you. The answers will point you in the direction of where you need to go.