The sister of US Senator Lindsey Graham will serve as his temporary replacement after the South Carolina lawmaker died from an aortic tear on Saturday.

Darline Graham Nordone was formally chosen by South Carolina Governor Henry McMaster on Monday, who introduced her as Graham’s “darling little sister” who would “finish his work for him now”.

“It is such an honour. Lindsey has always been there for me and now I will be there for him,” Nordone said.

The announcement came after officials, including President Donald Trump called for Nordone to serve as his replacement in a “tribute” to the senator, who never married and had no children.

Graham was close with his sister, who he legally adopted after their parents died while they were young.

McMaster said she would serve out the remainder of Graham’s term, which is set to end in 2027.

“Lindsey took care of his little sister,” McMaster said. “It’s my honor to ask his little sister, Darline Graham Nordone, to finish his work for him now.”

Nordone said she believed “this is what Lindsey would have wanted and I plan to honour him in this way”.

Graham died over the weekend due to an “aortic dissection” caused by cardiovascular disease, according to a preliminary finding by the Washington DC medical examiner. He was 71.

Graham had been running for re-election in November, and had the Republican Party’s nomination. Several other Republican candidates already have announced plans to run for his Senate seat.