My (M47) gf (F50) of seven years and I want to move in together. We waited this long because of our respective kids and the terms of her divorce agreement. She owns her house, I rent. She has a good pension and assets from before our relationship (RRSPs), but also her mortgage and other debts (a few thousand, nothing worrying).

If something happens to her, she wants her kids to get her house, which I think is fair. We've agreed that I should be her survivor beneficiary for her pension as the survivor benefits are more than liquidation to her kids. The question becomes whether her kids can subsequently turf me out of what would be my home without recourse.

If we spell out a mutually beneficial agreement, how likely will that hold up in court in the event of her death? Or the dissolution of our relationship if we break up? How can we protect ourselves and her kids if the court will just overrule any prenup?