Having achieved this extraordinary feat, she celebrated with a family lunch.
Wearing colourful hats, the group regaled each other with tales of her life while the centenarian gleefully feasted on her meal.
Daughter Lin Watson spoke on her mother’s behalf.
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“She always wanted to turn 100 and was thrilled to get the letter from the Queen,” she said.
“It was the first thing she said when she woke up – I’ve made it. I’m 100.”
Ms Watson said her mother originally came from Wales before she moved to England.
“We lived in Trowbridge, Wiltshire and mum worked two jobs and we grew up in a council house,” she said.
“She was very happily married until my father passed away at age 49. She has been by herself ever since.
Ms Watson said her mother probably would not share any secrets to long life.
“She eats like a horse, but doesn’t eat healthy. Loves cream and won’t eat vegetables or salad. She was raised on bread and dripping as a child,” she said.
Sam James, wife of Grace’s grandson Paul, considered Grace as her own nanny.
“It’s an amazing feat. She didn’t want to trouble anybody. She’s a very special lady,” she said.
“She has a huge appetite and she still lives with her daughter Lin and her husband Mike.”
They said most of the family was still in the UK but had sent through messages via social media.
“My children in England, Mandy with her children Brad and Jenna, and my son Nige with his children Issy, Charlie, Olivia and baby Edith all sent flowers, messages and a special locket,” she said.
Grace James was born on February 7, 1917.
At the lunch were special visitors for the occasion Shelia Marks who used to be Grace’s neighbour in Somerset, Lin Watson and husband Mike Twiss, son David James, grandson Adam James, and another grandson Paul with his wife Sam and their son (great-grandson) Jack James.