The mother-of-two from Belfast now faces treatment of both chemotherapy and radiotherapy.
A GoFundMe has been started by her friend Saoirse Ramsey with aim of raising £1,000. It only started yesterday - May 27, 2022.
In the appeal Saoirse explains that she is "fundraising for my friend Chelsea McCreight".
"In February this year Chelsea was diagnosed with stage 3 breast cance," she adds.
"Chelsea is only 28 and an amazing mum to two beautiful boys Riley age 4 and Rogan age 2.
"Chelsea has not got a lot of support due to sadly loosing her mum at a young age and her Dad being disabled.
"Chelsea now has to face chemo, radiotherapy as well as having both a Mastectomy and a hysterectomy".
The GoFundMe adds that the young mum will be "fighting the fight of her life to beat this and life now holds so many uncertainties".
"Chelsea is an incredible mum, daughter, sister, partner, friend and a whole lot more to so many people and her optimism and approach to this diagnosis is just extraordinary with two young boys," she adds.
"I want to do what I can to enable Chelsea to live her best possible life.
"The money raised will help Chelsea to do that - whether it’s through alternative treatment, private care, child care, house care, but mainly to enable life experiences to create wonderful memories for her lovely family, whilst going through treatment.
"I know times are tough for many and would appreciate even the smallest donation you could afford.
"I will post regular updates. Many thanks xx"
What is stage 3 breast cancer?
Stage 3 means that the cancer has spread from the breast to lymph nodes close to the breast or to the skin of the breast or to the chest wall, according to Cancer Research UK.
It is also called locally advanced breast cancer.
Staging for breast cancer is very complex.
Many different factors are considered before doctors can confirm it.
For example, they also use a sample of your cancer to test for: receptors for the female hormones
HER2 status (human epidermal growth factor receptor 2)
the grade of your cancer
You may also have a CT scan to check that the cancer has not spread to other parts of your body.