No lawyer here. I am only taking a stab at this because my family was wracked by a "lifelong tenancy" clause, and not in a good way. I also have deep resentment for those who marry for money, exploiting the widows and fatherless boys that Jesus spoke about for good reason.
So thats my problem.
No, that is not YOUR problem. Newsflash: You are not in the will!
Neither is the son's wife, apparently. Yet being married to the rightful heir to real property, she has more rights to that property than some, need I say it? Greedy "outlander."
If your wife has voluntarily vacated the house and it can be proved in court she has no need of it, she may have forfeited the tenancy provision. Probably not. Lifelong tenancy means exactly what it says whether she chooses to live there or not. The son cannot legally rent it out. He cannot sell it as long as she lives. He's still stuck paying taxes and upkeep on a property he can't make personal use of no matter what. It could be 20 or 30 years until he finally "comes into" his true inheritance. Until then, it can become a burden of sorts.
One thing is crystal clear: Your wife is not going realize a profit from the sale of the property. The son is the rightful heir, she was granted mere tenancy (which is actually a pretty sweet deal for her). Technically the property is already part of HIS estate.
Of course you can live there with her as her husband. When she passes on, you are out on your own. Best not to screw-up your relationship with the son and his wife so early on, because as it stands, he owes you NOTHING. Not a thin dime and no tenancy.
Although it looks like I am going to have to go to the Courthouse and see a copy of the will.
Uh-huh. The will that provides for the widow and her son. Not YOU.
Just one week after the wedding and your whinging: How can I exploit this widow's rights that she earned through a former marriage? How can I prevent her son from his rightful inheritance? What's in it for ME? Me, me!
Honestly, I don't see this (cough, cough) "marriage" getting off on a good footing. Learn your place and your wife and her family may feel obliged, through the sheer kindness of their hearts, to cut you a few in the end.
The very manner in which you handle yourself up front, please don't bet on it.
~Sue