His loving grandson, Mark Appleby, decided this milestone was the perfect occasion to "put a smile" on the retired Royal Navy officer's face.
So he set up a Facebook appeal with an aim to generate a flurry of birthday wishes for his grandfather, with an aim to receive 100 birthday cards by 28 December.
Little did he know that over 1500 cards, gifts and cheques would be sent from all over the world, including Canada, Australia and Vietnam, especially for Donald's landmark birthday.
Mark, 43, also a former solider, is absolutely delighted with the turnout and the happiness it brought his grandad. He told the Daily Mirror: "People sent gifts, money and cheques, which will all go to charity. He had such a fantastic day, he never stopped smiling."
Most of the cards were from fellow war veterans and their families who similarly understand the hardships of war and wanted to offer their thanks and support.
"The stories were really interesting. The thoughts from old soldiers of around the same age were so touching," Mark added.
Donald – who has 10 grandchildren and six great-grandchildren – lost his wife of 73 years, Eleanor, aged 95, four years ago.
He celebrated his centenary surrounded by family and friends at the Hallgarth Care Home, complete with a brass band.
Many happy returns Donald!
by Hannah Last
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