Jorja Carter and Alex Holland are a little bit different from their peers.

You wouldn't know it - both girls are happy and full of energy - but inside, things are not what they seem.

Jorja, 8, has already had two heart surgeries, the first when she was only three weeks old. She was born with three instead of four chambers of her heart and required a Senning procedure.

Her mother, Merise, said it was not until Jorja was born that the doctors were able to pinpoint what was wrong.

"The heart is just so small. They say when a baby's born, it's the size of a walnut, so imagine standing over that [in surgery] for eight hours."

Her second surgery, when she was 2 , was to put new stitches in her mitral valve.

Jorja also has heterotaxy, where all her organs are on the wrong side of her body. "Her heart is still in the right place, but even that is back to front."

Ms Carter said her daughter was "a very complex girl", but the surgeries had not stopped Jorja, who this year started to play netball.

"We won our first game 1-0," Jorja said.

Ms Carter said Jorja had been put at centre a few times because of her zippiness. "It's good for her to be normal, as such."

Alex was born with a heart block which caused her heart to beat slowly, only 60 beats per minute (bpm) while she was awake, and 30bpm when she was sleeping. Although doctors monitored it, she began to have fainting spells at 2 and had surgery to put in a pacemaker at the age of 3.

Her mother, Angela, said Alex would need to have surgery every four to five years to change the pacemaker's batteries and extend the leads which go from Alex's heart to the device.

Alex suffered almost no side-effects from the pacemaker, but was unable to participate in contact sports, in case the leads were severed.

Both Ms Carter and Ms Holland are on the committee for @Heart Nelson, formerly Heart Children, which is an organisation that provides support services to children with heart conditions and their families.

Ms Carter is a family support worker, helping families with heart children and running a coffee group once a month.

"Mums can just come and chat and ask about things they are concerned about."

@Heart also helped by providing travel grants for families who might have to go up to Starship children's hospital in Auckland, she said.

"It's nice for families to know someone else has been through that. Some mums have feeding problems, and I've been there, where your baby is losing weight instead of gaining it."

Ms Holland said she enjoyed supporting and meeting families in the community. @Heart was about supporting heart kids through life, so it was not just children, but teenagers and adults.

Both women had attended a conference earlier this year and met some adult heart kids, which was really special, they said.

"It's good for us as parents to see how they've coped," Ms Holland said."It's nice to know there's somebody else there who knows what you're going through."

The @Heart annual appeal is tomorrow and volunteers will be collecting at Richmond Mall, Stoke Countdown and in Trafalgar St, Nelson.

- © Fairfax NZ News