From the VSN governing documents:
"Only Owners who acquire their Vacation Ownership Interest directly from the Seller of a Network Resort or from resales brokered by an authorized resale company of Seller, a subsidiary or affiliated company of such Seller, or transferees of such Owners by will or intestate succession, or present or future children of such Owners who have otherwise succeeded to their parents’ interest are eligible to become members of the Network. In addition, Network Operator may, in its sole discretion and in some circumstances, transfer Network membership to an Owner’s immediate family member if the Owner has transferred title to the Vacation Ownership Interest directly to that immediate family member. Immediate family members mean the Owner’s spouse, domestic partner, children, brother, sister, parents and parent-in-laws."