First, you should seriously consider hiring Wisconsin counsel to assist you, as it seems you have strong feelings on the scope and end of your guardianship. That aside, what does "... who is soon to turn 18 in several months" mean, exactly? If it's more than 3 months, then surely in Barron County the matter can be filed, noticed, heard and decided; so if "several months" is that or longer, the answer to the first question is practically yes. The answer to whether or not you can petition seems straight forward as well, yes, you can petition for relief for almost anything. Now whether what you desire to do can be demonstrated to the court's satisfaction to provide you the relief you seem to seek (an extension on some grounds of the guardianship), that is another matter. What judge (branch?) are you before? What is the history of the proceedings. Does the minor have and/or threaten to have counsel if you petition for an extension? I am versed in these issues, I have appeared and am familiar with Barron County and I am available to assist, if desire. Please feel free to contact me at (715) 494-0080 for free, confidential, no-obligation 15-20 minute consultation.