Change of Custody for an 18year old?

[grazer]

My daughter turns 18years old this year. My attorney advises me that daughter will be required to sign a statement, stating her desire to change custody. Also attorney advises that daughter will probably be required to tell the judge in person of daughter's desire to change custody.

My ex/custodial mom, is totally against the change and has already begain a full out verbal/psychological assult on daughter to prevent her from changing custody. My ex is not wanting to give up the generous child support that she recieves.

Questions:
1. What wording would you use for the statement that daughter would
    be required to sign? or some short ideas?
2. Do most judges, when asking a child of it's desire to change custody,
    would the judge ask the child in open court or would the questioning
    be done in judge's chamber?
3. If questioning by judge of child's desire is done in judge's chambers,
    are opposing/my attorney allowed to be in the room during
    questioning? Or can I demand that no attorney's be allowed while
    judge is questioning?
4. How do you prepare a child for such questioning? Not wanting to
    brainwash child, not wanting child to tell lies, not wanting child to
    anything but tell judge of it's true wishes. But also wanting child to be
    prepared and not be intimidated by judge, opposing attorney, or the
    whole scene of coming to a judge/court room and be fearful. Judges,
    court rooms, attorney's and the whole system can be very frightening
    and intimidating to even adults.