“As a mother I do have concerns about her safety and that of the kids… she knows how I feel, that it’s risky,” Sally said.

Palin’s father Chuck said a man recently had sent the family photocopies of a receipt for a gun he had bought, together with a photocopy of a one-way ticket to Alaska.

The family had laughed it off, but the man subsequently turned up in the state and was arrested by the FBI, Chuck said.

“We sleep with the guns,” Palin’s father admitted.