Lily, of St Annes, greeted her guests from her bedside last Friday after being admitted to the hospital following a fall.
When asked how she felt to be 100, good-humoured Lily replied: "I feel fine. How do I look?"
Her son Derek Fagan organised the gathering after having to cancel Lily's birthday party, which had been planned at a hotel in St Annes.
He said: "It's wonderful that it's her 100th birthday today – it must be good genes.
"We are a bit disappointed, because three weeks ago she was full of energy,but she had a fall and broke her hip bone – and at her age it is an effort to recover. But the staff here have given her really good care and attention.
"They did her lipstick and her nails ready for today and made her feel very special."
For much of her life, Lily lived in Shildon, in the North East, before moving to a local apartment in St Annes, where she lived until three years ago. Then she moved into a rest home in St Annes.
Lily made a career out of ballroom dance teaching and she and her father had studios in Darlington, Bishop Auckland and Shildon. When she moved to the nursing home, Lily famously tried to teach the staff the cha cha cha.
She spent most of her life dancing, but during the war, when her husband was away, she worked in the local wagon works. To this day, Lily still has no grey hair and always has a smile on her face.