Ena Mackenzie-Smith is the head of five generations, with the youngest of her family aged four.
She spent much of her life raising her seven children including Jenny, who was adopted at birth, Lee, Lewis, Russell, Andrew, Scott and Samantha, as a single mother.
And she celebrated her centenary surrounded by her family at her home in Borehamwood on December 28, with those who could not join the party in person dropping in via video call.
Her son Andrew Mackenzie-Smith, 60, said: “There were quite a few family visitors on her birthday, including sons, grandchildren, great grandchildren and great-great-grandchildren, and she seemed in good spirits.”
“We had balloons all around the garden and garlands at the window. It was a good day.” he added.
Born in East Dereham, Norfolk in 1924, Ena weighed only three-and-a-half pounds and was so small she slept in a chest of drawers.
When she was young she moved to Cheshunt in Hertfordshire and during the Second World War worked with the Land Army in the green houses.
During this time she was nearly killed by a V1 Doodlebug, which exploded near a factory as she was walking by, Andrew said.
After the war, Ena moved to Ramsgate, Kent and got married.
But in the late 1960s she was left to bring up five of her children on her own and a few years later moved to Borehamwood, where she settled.
She suffered further ill fortune when her son Scott died of hypertensive heart disease in 2005, aged just 39, which left her devastated.
Ena survived bouts of pneumonia in June and in November, and her family hope she will soon be back on her feet.
Mr Mackenzie-Smith said: “It has been a hard life since 1968, but she and the kids grew up healthy although this has taken its toll in recent years. Even though she’s frail, she must have something strong inside to survive the pneumonia.”
He added: “Ena has always said that the secret to life was to take everything in moderation, not too much of one thing at once, and we guess that has worked out!”