Dolly Parton’s estate has accused her nephew of threatening to commit violence and destroy her legacy and business empire, and asked a judge to keep him away from its employees and business dealings.

Court documents filed in Nashville offer the first signs of discord in a carefully managed estate process for one of the most beloved personalities in music and beyond.

Bryan Seaver owns a company that provided Parton’s security detail. He was hand-picked by the star to announce her death at 80 from cancer in August.

The temporary restraining order request filed by She’s Alive – the entity that manages and protects Parton’s professional property and business, and other court documents – claims that Seaver sent increasingly threatening messages in recent weeks.

She’s Alive is run by Parton’s long-time manager, Danny Nozell.

Last week, She’s Alive sacked Seaver and Squadron Augmented Protection Services, saying his “terrorising conduct made their continued retention untenable”, according to court documents.

The court documents reveal text messages and emails She’s Alive says were sent by Seaver from just before Parton’s death.

They begin with threats to destroy the brand, and then after her death, depict Seaver revelling in his new-found fame and calling himself an “international arms dealer”.

“I’m going to set up a podcast dedicated to ruining Dolly’s brand partnerships and telling the violations these people have done on us. It’s going to be great. Or f—ing pay me,” he said in one message written on September 1 and included in the court documents.

Seaver also claimed that he worked for private military contractors overseas during the Iraq War and used that experience as part of these threats, according to the complaint.

The messages led to Parton’s trusts and estates lawyer leaving and employees of She’s Alive resigning, according to the court documents.

The entity has also had to hire private security for its staff, including at their homes, the documents state.

The restraining order is meant to stop Seaver from talking with or being within 300 metres of She’s Alive workers, lawyers and business partners.

It is also meant to keep him from interfering with its business relationships.

Parton wrote hundreds of songs, including classics such as Jolene, Coat of Many Colours and I Will Always Love You. They have had  more than 100 million worldwide sales and more than one billion online streams.