How to find out if siblings and I have financial inheritance from deceased grandmother?

My grandmother (paternal) passed in 2018 and her daughter (POA) didn’t mention siblings and I in her obituary as if we never were apart of her. Then younger sibling (from dad, not same mom) tells me she and 3 other siblings received $10,000 after grandma’s passing and select great grand children receive $25,000 after graduating. I’m trying to find out if the rest of my siblings and I were on the will and if we have a ‘hidden’ inheritance. We are grandchildren and had children before grandmother (paternal) passed way. Grandmother was integral and up to date in all areas of her life. I don’t see her leaving us out. We were well acquainted. Where do I begin?