Seventeen-month-old Tessa Evans suffers from an extremely rare condition where she was born without a nose.
“'At first I just couldn't understand it, I didn't even know it was possible,” she said.
Recalling the birth, Grainne said: “As soon as I saw her face I knew something was wrong.
“I was in shock and I just froze. The midwife cut the cord before I could even say anything and whisked her away from me.”
She said the first few weeks after her daughter was born were “the worst of my life”.
“I felt so lonely and helpless, I was supposed to protect my baby and be able to help but I couldn't. There were tubes coming out of her tiny little body everywhere,” she added.
Initially she was also so worried what people would think about Tessa’s appearance that she was too scared to even go outside.
However having researched her daughter's condition and sought support from a number of charities she found the confidence to get over people's prejudices.
"When we're out and about I'm no longer afraid of what people might think. In fact I think she will help people see that 'different' can be beautiful too," Grainne, from Maghera, County Derry, declared.
Tessa has suffered numerous problems related to her condition, including a hole in her heart and going blind in her left eye after surgery complications during attempts to remove a cataract.
The Daily Mail reports she also required a tracheostomy to be fitted to allow her to breathe while eating and sleeping.
Despite all of this, her mother claims Tessa is the “most determined little girl I know”.
"She adores her big brother and sister, copies everything they do and despite her 'disabilities' is already a typical toddler who climbs the furniture and loves to dance," she said.
"Everyone who meets her instantly falls in love with her, we just want her to inspire other people like she inspires us."
Tessa is due to have a prosthetic nose fitted at Great Ormond Street Hospital later this year.
The artificial nose will be replaced every few years as she continues to grow.
Grainne said she hopes her daughter’s story will inspire other families.
“I never want any child to be unloved or left alone because of their differences and diagnosis,” she said.
“I can't believe how much can change in a year. I was so worried about my little girl when she was born but she's defied all the odds and I am so proud and grateful to be her mummy.”
Grainne and Nathan have now set up a donation page for help in paying for Tessa’s care.