The 22-year-old is in the process of completing a nursing course and looking forward to a career in healthcare.
"She is so determined and focused on her studies and she was thriving so well before she was taken from us."
The pain of a missing loved one is almost unbearable for Gray and her family. Muriwai's disappearance has torn a hole in the whanau, and Gray says she is finding it impossible to cope.
"We're barely managing or functioning. It's like all time has come to a standstill," she told the Herald.
"As her mum I can't even think of my own feelings, all I can think of is how Breanna must be feeling out there, if she's cold, hungry or crying out for me to hurry up and find her. This is cruel and no one should ever have to go through this."
She believes there are people in the community with information about her daughter, and is urging them to tell police anything they know.
"We ask that they please do the right thing and come forward, just imagine if this was one of your loved ones, one of your children, your grandchild or niece? If you're afraid to come forward, call in anonymously and just let us know where she is, that's all we want, we just want her home."
Gray said she is incredibly grateful to the community which has come out in support of her and her family, and that it will "take a village" to bring her daughter home. The case has been shared widely on social media, and Gray wants that to continue as much as possible.
"We have more than 150 missing people in New Zealand and this doesn't seem to get the attention it needs," she said.
"Let's bring awareness to our missing persons rate and help find our loved ones."
For her missing daughter, Gray had a message of hope.
"If you're able to see this, just know me and Nan are searching high and low for you and we're never giving up but, we know you'd already know this. Stay strong bub, we'll find you and bring you home."
