Henry McMaster, South Carolina’s governor, appointed Lindsey Graham’s sister, Darline Graham Nordone, to replace him in the Senate following his death on Saturday, after Donald Trump recommended that she be given the role.

Her appointment was welcomed by lawmakers from both parties, who saw Nordone as an appropriate replacement for the brother who had raised her after their parents died when she was a teenager.

“Lindsey took care of his little sister in years long departed. It’s my honor to ask his little sister, Darline Graham, to finish his work for him now,” the Republican governor said at a press conference convened at South Carolina’s state capital in Columbia.

Surrounded by the grieving family and friends of Graham as well as Tim Scott, who is now the state’s senior US senator following his colleague’s death, McMaster called Lindsey Graham an “irreplaceable” and “extraordinary” man.

In brief remarks Nordone, 62, said: “Lindsey has always been there for me, and now I will be there for him”.

She offered no hint of deviation from her brother’s politics, and made note that she would join the ranks of Trump’s allies in the Senate.

“I promise to work hard over the next several months to support the president and carry forward the efforts of my brother on behalf of the citizens of South Carolina and the United States,” Nordone said. “I think this is what Lindsey would have wanted, and I plan to honor him in this way.”

Closing with a personal message for her late brother, she said: “I miss you more than I can even put into words, but I’m going to do this. I got it.” The newly appointed senator and McMaster departed, without taking questions.

Nordone had earlier in the day picked up the support of Trump, who wrote on social media: “I recommended, to Governor Henry McMaster, Lindsey Graham’s wonderful sister, Darline, to serve as interim Senator from the Great State of South Carolina. This would be a fabulous tribute to Lindsey, who loved her dearly!”

The governor said at the press conference that he had offered her the job early on Sunday morning, after her brother’s death was announced, and she accepted “through tears”.

A commissioner at the South Carolina Commission for the Blind, Nordone is a trained optician who has previously been employed by Clemson University and the state’s department of employment and workforce, according to a biography distributed by the governor’s office.

She is the president-elect of the National Council Of State Agencies For The Blind, as well as a member of South Carolina’s workforce development board.

Nordone was known as having a close relationship with her brother, who became a surrogate father to her after the deaths of their mother to cancer, and then, 15 months later, their father to a heart attack, when she was a teenager.

Nordone introduced her brother at the rally in 2015 where he announced his bid for the White House, and Graham later said he could envision a role for her in his future administration.

“If she took a role on, she would be a great representative of our country. I can’t think of a better person to represent our country in an event than my sister,” Graham told CSPAN.

The Senate majority leader, John Thune, welcomed her appointment, saying: “Lindsey’s legacy will continue through Darline, and I look forward to welcoming her soon.”

James Clyburn, the longtime congressman who is the sole Democrat left in the South Carolina delegation, congratulated her on the job, adding that “it is my hope that we will continue to diligently work together as we have in the past.”

“I wish her success as she takes on this new role, and I have confidence we will use every opportunity in the months ahead to do all we can to help make America’s greatness accessible and affordable for all.”

Nordone can serve as senator until next year, when the term her brother was elected to in 2020, his fourth, expires.

Republicans will hold a special primary on 11 August to choose a new Senate nominee, who will face off against Democrat Annie Andrews in the November midterms. South Carolina is a strongly Republican state, and analysts believe whoever the party nominates will be favored to win the seat.