My mother excluded me from her will — before she died, my sibling cashed out her annuity policy, on which I was a beneficiary. Should I sue my family?

Dear Quentin,

My mother recently passed away and I was written out of the will, except for a small amount. She and I had several disagreements over the past two years. This change of will occurred 15 months prior to her death, with her executors present. The remainder of her estate is being divided between my siblings. 

My…