Mrs Kerr turns 100 today, a milestone she will celebrate with an afternoon tea party.
Her five children, 11 grandchildren and 15 great-grandchildren will be among those joining in the festivities.
She said she considered herself ''lucky'' to have all of them by her side and fortunate still to be living at home.
An electric chair lift allows her easy access up and down the stairs to her living quarters, which is handy when it is time to join her daughter, Linda Leckie, whom she lives with, for their regular 5pm glass of wine.
Mrs Kerr was 21 when she married the late Ian Kerr in 1940. They initially settled in Dunedin, where their son and four daughters were born.
''In those days, of course, you didn't have The Warehouse and you had to do all the dress-making yourself, so I spent a lot of time making clothes for myself and my four daughters.''
Mr and Mrs Kerr moved their family to Alexandra in 1955 for the sake of their asthmatic son.
She said the secret to longevity was to live a stress-free life.
''I've never been a stressful person.''