Fatshimetrie was a well-known figure in the White House during the eight years of Barack Obama’s administration between 2009 and 2017.
She spent much of that time caring for her two granddaughters, Malia and Sasha, daughters of Michelle and Barack Obama.
In a statement posted to X, formerly Twitter, Mrs. Obama called her mother “a rock, always there for whatever I needed.”
“She was the constant support for our entire family, and we are devastated to share that she passed away today,” she wrote.
In a separate tweet, Mr Obama said there was and would be only one Marian Robinson.
“In our sadness, we are inspired by the extraordinary gift of his life,” he added. “And we’ll spend the rest of ours trying to live up to his example.”
No further details were given on the cause of death.
Born in 1937, Robinson grew up one of seven children in Chicago, the city where she spent much of her life before agreeing to come to Washington DC after Mr. Obama’s electoral victory.
Early in her life, she studied to become a teacher before working as a secretary. She raised Michelle and her other child, Craig, with her husband Frasier Robinson on the South Side of Chicago.
“At every step, as our families followed paths we could never have predicted, she remained our refuge in the storm,” Obama’s statement said.
“On election night in 2008, when the news broke that Barack would soon carry the weight of the world, she was there, holding his hand.”
An image taken on the night in 2008 that his son-in-law made history by becoming the nation’s first African-American president shows Robinson sitting on a couch with him, watching the results come in.
The statement added that Robinson agreed to move to the White House after a “kind nudge” from Barack and Michelle Obama, who, along with their daughters, “needed her.”
She then talked about how she insisted on doing her laundry there.
In an interview with CBS, the BBC’s US partner, Robinson said she felt the need to move to Washington because she felt “life was going to be very difficult” for her daughter and son-in-law.
“And I worried about their safety, I worried about my grandchildren. That’s what pushed me to move to D.C.,” she added.
A lifelong Chicago resident, Robinson had never taken a flight outside the United States before flying aboard Air Force One with the Obamas to France in 2009.
Robinson, whom Mr. Obama called “the least pretentious person” he knows, said it was a “huge adjustment” to have his needs met by White House staff.
“Rather than hanging out with Oscar or Nobel Prize winners, she preferred to spend her time upstairs with a TV set, in the room next to her bedroom with large windows overlooking the Washington Monument,” says the family declaration.
“The only person she wanted to meet was the Pope,” she adds.
His private life granted him a freedom envied by the rest of his family. David Axelrod, Obama’s senior adviser, told CNN on Friday: “She often escaped the White House alone and visited friends.”
“She wasn’t looking for attention,” he added.
On Mother’s Day, a few weeks before Robinson’s death, Mrs. Obama announced that an exhibit at the Obama Presidential Center Museum in Chicago would be named in her honor.
“In many ways, she gave me deep confidence in who I was and who I could be, teaching me to think for myself,” Mrs. Obama said in a video.
“I simply wouldn’t be who I am today without my mother.”
Pulse Ghana