Surrounded by her friends at a care home, it was a reflection of Jeannie's popularity that so many people were so keen to offer their congratulations.
Despite having to overcome tragedy in her long life, she has maintained her spirit and vitality.
Jeannie was brought up in Parkhead, Glasgow, and worked in a nursing home in Great Western Road.
Her husband, John, was in the Navy but was killed as he returned from the Second World War.
Jeannie said: "I remember getting the telegram. I have lovely memories of my husband.
"I met him at his brother-in-law's wedding. When we clamped eyes on each other during the ceremony, that was it.
"When he died, I was bitterly upset, of course, but I had to be strong to focus on raising my son John jr. I had help from family and friends and John turned out fine."
Sadly her son passed away three years ago.
She said: "He was my pride and joy. Even growing up as a single mum he was never a burden. I have a picture of him and my husband on my nightstand.
"He was my only boy, my greatest achievement."
And after such a long life Jeannie has only one complaint – the loss of her "gorgeous jet black hair".
She said: "When my hair colour went grey, maybe then I panicked a bit about my age – for about five minutes."
Jeannie's birthday celebrations kicked off with a variety performance followed by cabaret. There was also a buffet and cake to help celebrate the milestone year – and lemonade.
Most of Jeannie's close family have pre-deceased her and she has formed a strong relationship with the residents and staff at Sherbrooke Lodge, Pollokshields. And she insists there's no secret to aging gracefully.
She said: "I keep active and I've been teetotal for as long as I can remember. The residents and staff here are my family so I have a good laugh with them."
Home manager Jackie Fenn said: "It's always a special occasion when one of our residents turns 100. We all wish Jeannie a happy birthday."