Resolved Question: Can my great-aunt kick us out of our house?

My grandmother died Thursday and her will clearly states that her house and a trust fund are to go to me, my (regular) aunt, and my uncle, but my great-aunt, who is the executor of the will, says that we have to get out of the house by Monday or she is calling the law. The will states that the house is ours but she says it’s not until we go to probate court. I know perfectly well my grandmother had no outstanding debts because she spent months paying them off with her late husband’s life insurance money after he died of cancer so I know my great-aunt won’t have to sell the house, and she has frozen the trust fund already. She even came over to the house and said that she wanted my grandmother’s TV, computer, her van, and my grandfather’s tools (which had been willed to my uncle by my grandfather). My grandmother was just buried today and yet my great-aunt started all this an hour after my grandmother died and she even stole $8000 from my grandmother’s checking account (which was supposed to go into the trust) and she did this without even showing the bank a death certificate. I know she can withdraw money for funeral expenses but my grandmother had already paid for her funeral in advance too. What can we do? Is she just trying to scare and bully us?
I do know she wants the house and trust fund for herself too.