Myia, from Lucan, was two when she was diagnosed with spastic diplegia, a form of cerebral palsy, which affects her mobility.
Her mum, Annemarie, has been researching specialised treatment options for more than two years and she told the Herald of her delight at learning the operation would finally go ahead.
"Myia first travelled to the University of West England in Bristol last January for an initial consultation," she said.
"They put her through testing to see if she was right for the operation."
Annemarie rang the HSE on December 14 and was told the good news that the surgery would be funded.
"It was so exciting to find out just before Christmas," she said.
Things have moved quickly since then and the family has a date for January 6.
"The following day, Myia has the pre-testing, and on January 8, she will be having the operation," she said.
The selective dorsal rhizotomy (SDR) operation will increase Myia's balance. At the moment, she has to use leg splints, a walker or a wheelchair.
Her mother said that the treatment will give her another 50pc balance on top of what she has, and get rid of her leg braces.
"That's a big thing for a little girl, because we can't get a lot of shoes that fit her with the splints, and they have to have a strap," she said.
"She is a size 12 and she has to wear a size two and a half because of the splints taking up so much room, supporting the foot."
After the operation, she will be able to wear slippers for the first time.
Annemarie and her husband, John, have four other daughters: Shannon (9), Kayleigh (5) Laila ( 2) and Isabella (1).
The family know that it will be at least seven or eight months before Myia will be able to walk unaided.
But she is looking forward to playing games with all of her friends.
"She knows she is going for an operation. Her friend had it and she has seen the recovery," said Annemarie. "She is excited that she will be able to play hopscotch."
The family are still fundraising for the €26,000 needed for her aftercare.
Myia will be in hospital for three weeks, and will need aftercare for two years.
And she will require intensive physiotherapy five times a week for the first six months.
The local community has rallied around, and fundraising efforts have succeeded in raising €17,000 so far.
Meanwhile, one of the highlight's of Myia's year was meeting Olympic boxing champion Katie Taylor.
"She got a signed glove from all the Olympic boxers," her mum said.