Expiration date...on the seller?

When offering on a home our purchase agreements have all sorts of things covered including expiration of offers and such. We offered, they countered, we accepted counter and proceeded towards close. One thing I didn't see coming was the expiration of the seller. Two days before our closing the seller passed away. Didn't see that coming. I was a little ashamed that my first thought was my buyer's inconvenience. I think we tend to be so focused on what fires to put out to get to a closing we lose sight of the players. RIP seller, although I never met you, I wish you peace. Now I will be learning the probate process as I continue to focus on my buyer but will definitely always remember this one. Best of luck in all you do and thanks for reading.