Question: I purchased an Xbox Live Gold Pass and it went under my parental profile, not my son's profile. Since he is the one who actually plays Xbox, how do I give him access?

Answer: 
There is no way to directly transfer a Gold membership from one person to another. However, if you purchased a one-year Gold membership, you CAN cancel it and get a pro-rated refund, and use the money to buy the gold pass for your son. Call Xbox Support in your region and ask specifically to end your Gold membership. They will try to talk you out of it, but be insistent.

Alternatively, you might consider getting a Gold Family Pack account. It costs less than two Gold memberships, both of you will receive the gold membership and your existing gold membership will be converted into a pro-rated extension of the Family Pack membership.
I don't think you can do this. I can't find any official FAQ documentation, but going on a number of answers to this question on different forums, it looks like once it is linked to one account it can't be transferred. Sorry :/

You could send [Xbox Live Support](http://support.xbox.com) an email and ask them nicely...