Legal advice needed about probate

[Robin Wilk]

Okay here's my situation I live in Pennsylvania. My step-grandfather (My paternal grandmother's common law husband)passed away in October 2015. Now, I was not named in the will but I do have a copy of it. I would like to know if I have a claim on the home my grandparents had purchased together in 1985. As far as I know the deed of the home is in both of their names. My grandmother passed away in 2003 and as far as I know her will was a rights of survivorship will.

Can the home go through probate? What are my chances of being able to obtain the property? I can explain more if needed. I'm thinking that I may not be able to obtain it at all but I just wanted to get an expert opinion. Thanks for your time reading this and any advice you can give me.