Dolly Parton's Nephew's Termination Letter Revealed Amid Estate War

Dolly Parton's nephew wasn't just fired as security for the singer's properties ... he was ordered to stay away and told to have his personnel “peaceably vacate the Properties at once” ... TMZ has learned.

TMZ obtained the letter Bryan Seaver received terminating him and his security companies following "changes in ownership of the Dolly Parton properties."

The letter gets right to the point ... telling Seaver that he and his companies were "formally dismissed and terminated and he's not to be on any of Dolly's properties, effective immediately.

According to the letter, replacement services had already been lined up ... and Seaver was instructed to inform his personnel to "vacate the Properties at once."

The letter says this decision was made by the DP Dean Trust Group for "the protection of the Trust and beneficiaries as a whole."

It continues to say the co-trustees will be in contact with Seaver about his interest as a beneficiary "in the near future."

As we previously reported, Dolly's professional-property entity, She's Alive, LLC, has filed a lawsuit seeking a temporary restraining order against Seaver.

The lawsuit accuses Seaver of threatening behavior and allegedly trying to pressure the company and trusts for money.

Seaver and his team previously told TMZ they were "dismayed by the unexpected and, so far, unexplained actions" taken after Dolly's death. His team also said they remain committed to protecting her family and legacy.