Even with family, it's safer to have a written contract and use a real estate attorney or title company to handle the deed [11, 30].
"Hey! Just curious, have you and Mom/Dad ever thought about selling the house? I’ve been looking at homes lately and honestly, I love yours. If you’re ever ready to move, let me know first!" The Serious Discussion
Your parents can "gift" you part of the home's value to help with your down payment, which is a common perk when buying from family [19].