How do I file a creditor's claim against my grandmother's estate?

4 years ago I gave my grandmother a cashiers check for $10,000 to hold on to for me for a rainy day. When my teenage son was murdered in June of 2018, I developed severe PTSD and have not been able to work in my previous capacity. My grandmother and I worked out a budget spanning a year and she cut me a check for $3900, which I used to catch up. The remaining $6302 was to last me 3 maybe 4 months, at least into the new year when I was set to start a position with the Department of Commerce. My grandmother's health declined very rapidly and before I knew it, she was gone. I was unable to secure the final payment and remaining balance of the $10,000. I am the black sheep of my family and although it was well known that gram had been helping me and the paper trail completely validates ever I have been told by the Executer that she will not give me any money. My Aunt was named Executer and trustee. I have a 16 year old daughter to whom my grandmother left a 2011 Hyundai Tuscan.