The 29-year-old started suffering from headaches and eye-problems around six weeks ago
. A routine blood test revealed abnormalities in her liver enzymes and bones and Ms Allen, of Annfield Plain, County Durham, was referred to University Hospital of North Durham.
Ms Allen didn't even have chance to say goodbye to her children, dying just a day after the shocking diagnosis The part-time office administrator had further tests and was then sent to a lung specialist, but her breathing became poor and she was admitted to hospital.
She was allowed home over the Easter period but was back on a ward after she continued to struggle with her breathing. On Wednesday April 3 she was diagnosed with advanced lung cancer which she was told had spread to her spleen, liver and glands in her neck.
Ms Allen had been due to be godmother to her nephew, Austen. Her funeral will now take place in the same church that his christening was arranged for
Kirsty with daughter Ebony. 'She was a beautiful person both inside and out and she will live on in her children,' said her mother Wendy 'She had never smoked in her life, she never touched them. She was so healthy and went to the gym and liked keeping fit.
The doctors said it was probably because her hormones were at their peak that the cancer happened so quickly. 'Kirsty lived for her children. She wanted to get through the chemo so she could last another 10 years. 'Adam is only two and she thought if only she could get him up to 12. But she died the next day.
'I am making a memory box for the kids, she said she didn't want them to forget her. 'It is so difficult, I have cried for a week but Ebony says some sweet things that are keeping us strong.' Ms Allen was preparing to be a godmother to her brother Karl's five-month-old son, Austen. The christening had been planned for April 21 at St Joseph's Church in Stanley, but has now been cancelled. Instead, her funeral will take place at the same church on Monday.
Ms Allen's mother added: 'She was so looking forward to being a godmother. 'Instead we are holding her funeral -something I never thought would happen. 'She was a beautiful person both inside and out and she will live on in her children.' Her daughter Ebony said: 'I will miss her cuddles when she tucks me up in bed and when she wraps her arms around me.
I have drawn her an Easter card and my little brother did too and they will be sent to heaven with her. 'I also have a love-heart and I wrote inside "I love you mammy, you are beautiful, love from Ebony". I wrote it all by myself. I will really miss her.'
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