The singer, 39, and her musician husband, 73, were left reeling when the carer for their 2-year-old son Rennie died after she was struck on August 9 at a Toyota dealership in San Fernando Valley, California.
TMZ is now reporting Yadira Colito was killed while waiting for her car to be serviced.
It added an 84-year-old woman drove her white Toyota RAV4 into the covered service bay driveway. Authorities at the scene said the driver mistakenly hit the accelerator instead of the brake.
TMZ said Colito was “pinned under the SUV and dragged for about 20 feet” before bystanders helped free her.
The Toyota dealership where the nanny died has called her death a “heavy burden”.
Megan Maybee, the Hamer Toyota dealership’s director of communications, told Us Weekly in a statement: “We extend our deepest condolences to Yadira’s family, friends, and loved ones during this incredibly difficult time. The loss of such a vibrant life in such tragic circumstances is a heavy burden to bear, and we share in their grief.”
McPhee has announced she had to rush home from her and her husband’s tour in Asia due to “a horrible tragedy”.
She told her Instagram followers: “Dearest Jakarta fans, it’s with heavy heart I announce I have to miss our final two shows of our Asia run.
“David and I have had a horrible tragedy in our family and at least one of us need to get back home to our family.
“Please know how sorry I am and how much I wish to return one day and perform for you all. Love Katharine.”
Foster was still able to take the stage for the final two shows on their tour, and shortly after McPhee’s post it emerged the tragedy she was referring to was the death of their nanny.
The Duke and Foster reportedly have a “really beautiful” and “cute” relationship, said Foster’s wife McPhee, who went to school with Meghan Markle.
Foster is known to have facilitated arrangements for the Duke, Duchess and Archie to stay at a waterfront mansion on Vancouver Island, now known to have been used as a half-way house on their way to Los Angeles.
The retreat, in which they spent six weeks as they negotiated their departure from Britain and royal duties, allowed them to find “respite” from their public lives, Foster said.
“David is the resource guy. He knows all the places. He loves to help people.
“We just hope they end up somewhere where they feel like they can really settle down.”