Granny passed 2daughter one daughter passed so property and house split one daughter. And grandchildren of the one passed

Im not sure I follow your story as the punctuation and number choices are confussing I think I gathered That your grandmother passed. After she passed she left a home to 2 daughters. One of those daughters, your mother passed. If this is the case, yes your mother's children owned half of the home. Unfortunately, if no probate was ever filed, there is nothing on the record as to who has ownership. You need to speak to a probate attorney to get everything sorted out.