Thanks for your response. Legally, the answer is, yes, you do have the authority to sign on behalf of your son. There are a couple of issues, however, that I should bring up. One, even though you are legally authorized to sign on your son's behalf as guardians, you might want to confirm that your lender is willing to allow it. Some lenders may want some independent authority, like a court, to issue approval in order to refinance the loan. Banks tend to be very conservative, as well as title companies issuing the mortgagee's policy, and so it's a good idea to get this addressed up front. Two, since your home is owned 1/2 by you and 1/2 by your son, you do have a fiduciary duty to your son with regard to his interest in the house. Thus, the use of the proceeds, 1/2 of which are legally his, can create a problem for you down the road when he becomes of majority age, if he contests that you used funds for some other purpose other than his benefit. So, that's just something you want to be aware of in your relationship with your son.
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