Media playback is unsupported on your device Media caption Children cared for at a south Wales hospice will be remembered through birdsong.

For 19 captivating seconds, Abigail Harvey's family listen intently to the song of a robin. They're sitting in the sunshine of the memorial garden at the hospice where Abigail spent many happy hours.

Ty Hafan's children's hospice, just along the coast from Barry Island in south Wales, holds a special place in their hearts. And now, as part of a remarkable new sound installation, the names of more than 300 children who were cared for there will be celebrated in the form of birdsong.

Abigail had mucolipidosis type 2, an extremely rare, life-limiting disorder and died at the hospice when she was 10.

Image copyright Paul Fears Image caption Abigail's mum Pauline says the family has happy memories of Ty Hafan

Speaking to BBC Radio 5 Live, her mum, Pauline Harvey, says: "Ty Hafan was the only place we could be together as a family, outside of our home and the hospital, because Abigail had such a severe disability."

The hospice has always remembered children who have died by painting a pebble with their name on it, but now they are using Morse code and birdsong to do something special for hundreds of families.

"We knew from the parents that hearing their child's name is very, very important, so we found a really creative way to link those children's names into a very natural feeling of the birdsong in the environment," Tracy Jones, head of community services and partnerships, explains.

The hospice is working with sound artist Justin Wiggan, who takes the name of the child, puts it into a Morse code translator and then samples birdsong around it.

Image caption Justin told BBC Radio 5 Live he's using a calendar of birdsong to decide which bird to match with each name

Justin says it's been an emotional process. "I don't think you can create work like this without being connected with the people and families - I am a father myself so I can identify with some of the age ranges. The first few times it is quite overwhelming."

He has a detailed way of choosing which bird should sing each child's name. "I started to look at a calendar that I found in an old book in a charity shop, showing which birds sing the strongest during the month that the child died.

Image caption He uses the bird which was singing the loudest in the month when the child died

"From talking to parents and just seeing how at times the child was a lot stronger than the parents, this carried through to a concept that the bird chosen for the child should be the one that sings the strongest during the month that the child died."

And he has what he admits is a romantic hope that wild birds in the garden will, in time, mimic the sounds.

Pauline says Abigail would have been delighted with the concept. "She was so happy, and such a big personality that she would love the idea of having her name sung across the skies - she would absolutely have adored that idea."

Image caption Abigail's family say a robin suits her very well

Abigail's name has been turned into the birdsong of a robin, which Pauline says is very appropriate. "The robin is one of her favourite birds, such a lively, stroppy, opinionated little bird, it's very emotional."

And hearing it played out in the garden for the first time? She takes a deep breath, then smiles. "It sort of knocked me off my feet a little bit. I think what I'm hit with is a wall of memories."

Abigail's dad Stephen agrees. "It's a fairly small bird, and Abigail was small for her age, she was probably the size of a two-year-old. She was extremely feisty, it just brings a lot of emotions and thoughts back."

Image copyright Harvey family Image caption The family will have the birdsong at home so they can hear it every day

Abigail's sister Jennifer, 11, was seven when her sister died. "It's one of those birds that will not be forgotten, you will always know what it is, and Abigail will not be forgotten at any time."

The Harvey family will also be playing out the recording on a speaker in their own garden.

For Jennifer, having the birdsong at home will be a comfort. "When I wake up in the morning and go outside. Just to hear that, that would cheer me up a lot."

Abigail's story was featured on 5 Live's Anna Foster programme which is broadcast from Monday to Thursday from 10:00-13:00 BST and is available on iPlayer afterwards.