Mark and Audrey are married and both in their 60’s. They have $1 million in a securities account as joint tenants with rights of survivorship. Mark starts to date Stephanie, a 20 year old woman. He gives Stephanie his interest in the account as a gift. Five years later, Audrey dies. Stephanie and Audrey’s sole surviving heir Joanne claim Audrey’s share of the account. Who wins and what are the policy reasons behind the controlling rule?