Mum has sixth child so she can save her older son's life with bone marrow

A Melbourne couple have admitted they only had a sixth child so they could save the life of their fifth child who has a rare genetic disease.

Olivia and Andrew Densley from Melbourne discovered little Fletcher, now 4, had Wiskott Aldrich Syndrome, when he was a baby. It's a rare condition that means he has an abnormal immune system and cannot form blood clots. 

'When your platelets are really low, it causes your blood to leak. The concern is that if those levels continue to get lower, your body can just spontaneously bleed internally,' said Olivia late last year.

'If that happened and he started bleeding on his brain there’s not a lot that can be done to come back from that.'

Last night on Channel 9's 60 Minutes, the couple admitted that they made the controversial decision that to save Fletcher's life, they would have a sixth child who would be genetically engineered.

The couple have no regrets with their decision to have a sixth child, despite the disapproval of friends and public backlash.

'Olivia's a bit more sensitive to what other people think and say but I don't really care, I'll just live my life and you live yours,'' Mr Densley said on the show.

Fletcher's older brother Cooper, also suffers from the disease but his life was saved by another sibling, Jackson. Sadly, none of Fletcher's other brothers or sisters were a match for him.

The couple spent more than $140,000 on IVF to create the perfect baby, who was the perfect match and on August 2, Olivia gave birth to little Lilliahna.

'We can positively say to this child, yes, we did have you for some of your bone marrow, but it's a good thing because we knew you were going to be OK,' Olivia said.

But although Lilliahna is a match, the Densleys have to wait until she is 10kg before the bone marrow transplant can take place and even then there is no guarantee the operation will be a success and Fletcher's life is saved. 

The reaction to the family's plight was mixed on social media with many people branding the Densleys as selfish.

'Why go risk an unhealthy 5th. Some people cant even have one child. Then to spend over 100 grand to have a healthy 6th just to save the 5th that they shouldnt have had,' one person commented.

But others admitted they would have done the same.

'You do anything you can to save your children - we all would,' said another. 

You can find out more about Fletcher and the family here