Pay the IRS: that's how you protect it. Once you are aware of a potential debt, any property or asset transfer, unless it is for fair market value (e.g. your father or nephew paying your brother the fair value of his interest in the property), will be seen as "fraud" on any actual or potential creditors (like the IRS) and can be voided, or undone, so that the creditors can get to the property. You can't transfer ownership to avoid a known debt or obligation.