Nine-year-old Hannah Donnelly is working out a new secret handshake with her eight-year-old sister Katelyn. Eleven-year-old sister Shauna sits on the sofa and laughs.
"Something we made up in the car," smiles Hannah going through the routine that would impress their idol Miley Cyrus.
Today's a good day for Dundalk girl Hannah, she can move with just her "normal pain". On a bad day she is in terrible discomfort. The simplest thing like getting out of bed causes excruciating pain.
"I'm always sore, it's my normal pain," she explains.
Since she was a baby, Hannah has battled a rare life-threatening disease that affects her auto-immune system.
The condition had gone undetected for seven years, until last Christmas when doctors diagnosed the rare genetic condition called Muckle-Wells Syndrome. In the US it affects 300 adults and children.
The Donnellys think Hannah is the only child in Ireland with it. But Hannah also has Benign Hyper Mobility Disorder and Chronic Pain Syndrome.
The sum total of her condition means there is no definitive medication to treat her and no understanding of any long-term prognosis.
It is all characterised by temperature flare-ups causing a rash all over her body. Along with that there are joint pains, eye-inflammation, loss of weight and general immobility.
Shauna says she worries about her sister. "We take care of her, look out for her. We carry her bag to school and if we are going for a walk, we slow down."
Hannah opens her locket, the one she's had since childhood. She shows it to me -- Our Lady's face is on one side, Hannah's baby face on the other.
She smiles: "When I am sore I turn to my sisters and to Our Lady. When things are not great I say I know Our Lady will fix it for me."
Next month, Hannah will travel to Lourdes with her mother Teresa. It will be their third visit. This time they will be praying for a medical breakthrough.
Hannah is looking forward to the trip. "I felt like I was being blessed -- that Our Lady was making me better."
Dad, Paddy says: "Hannah has a life but not like normal kids. She was in pain from the day she was born."
If she gets a flu bug, she is hospitalised -- her system cannot take the infection. When she is well enough to attend school, Hannah sits on a special soft chair, to help ease her pain in her joints.
Teresa says: "One day when Hannah was two she developed a high temperature and her heart beat was racing and she looked very lethargic. Her body was covered in a rash and my first thought was 'meningitis'."
Teresa took their daughter to Our Lady of Lourdes Hospital, Drogheda. "The tests came back to say it was something viral."
Four months later the rash came back. "Paddy thought it was something to do with teething," says Teresa. "But Hannah was also sweating a lot and when she did this, the rash seemed to go away afterwards."
At the age of four, Hannah had a swollen leg which was x-rayed. Again the diagnosis was a viral infection. She was given antibiotics and pain relief.
"At this stage Hannah was getting worse. She was losing weight and her hair started to fall out," says Teresa.
From then until the age of six it was a constant trip to the hospital, and a fight for the illness to be recognised. It was a lonely place for Paddy and Teresa. They knew nobody else in their situation and they feared for the worst.
"One day I put Hannah into the car and took her back to the hospital in Drogheda.
"She was admitted and her temperature never went below 104 degrees. The paediatrician who examined Hannah told us 'you have one very sick girl'."
The family met with Dr Orla Killeen, in Our Lady's Hospital, Crumlin. "Hannah would not be here today only for her," says Teresa.
Then a specialist from the UK came over to Dublin this Christmas. "He said he felt it was classic Muckle-Wells Syndrome," says Teresa.
Hannah will now face a series of injections in an attempt to ease the episodes and the pain. Teresa says: "We are very nervous about the injections -- but we are more nervous about doing nothing."
-- Skin rash, fever and joint pain.
-- Recurrent flare-ups that begin in infancy or early childhood.
-- May be triggered by cold, heat, fatigue or other stresses.