Euthanasia group backpedals on claims Fernando Manrique contacted them for suicide advice.

Warning: This post contains details of suicide and may be distressing for some readers. If you need help, please call Lifeline on 13 11 14.

High-profile euthanasia advocate Phillip Nitschke has backpedalled on claims that the father of the family-of-four found dead on Monday had previously contacted his organisation for advice on suicide.

Fernando Manrique is believed to have rigged up an elaborate gas chamber in his Davidson home where he, his wife Maria Lutz and their two severely autistic children, Elisa, 11, and Martin, 10, children died on Sunday.

Nitschke earlier told The Australian that Manrique downloaded his e-book The Peaceful Pill Handbook, which includes a chapter about suicide by carbon monoxide poisoning.

But the controversial doctor has now changed his story.

Speaking to Fairfax this morning, Nitschke said when he re-checked his organisation’s database, he discovered it was a different man with the same surname that had, in fact, downloaded the e-book.

“Fernando Manrique did not access our book,” he said.

Nitschke’s organisation, Exit International was founded in 1997, under the premise that suicide is a fundamental human right.

It’s a stance that’s earned Nitschke the nickname “Dr Death”.

Philip Nitschke has backpedalled on claims Mr Manrique contacted his group.

Manrique reportedly set up an elaborate system of pipes throughout his ceiling, a system so elaborate, police sources have said it must have taken much pre-planning.

Whether this was a suicide pact between a husband and wife or a murder-suicide, authorities are still investigating.

Manrique, a business executive, was found dead in one room while his 43-year-old wife was found dead in bed with their daughter.

Their son was found alone in his bed in a separate bedroom.

Both children were autistic, deaf and mute.

Ms Lutz pictured with Martin and Elisa. Via Facebook.

Dr Nitschke earlier told the media he had “never had a situation to my knowledge where a family has come to us wanting advice on how to end all their lives, and obviously if that did happen, we would be very cautious”.

“The surprise to us was that given this family is from Bogota, which is one of the few places in the world where you can buy ... ­suicide drugs ... over the counter, it’s a surprise that he used carbon monoxide,” he said.

“But they knew about carbon monoxide, so on the other hand it looks like somebody went to a great deal of trouble to make sure the death was peaceful.”

Manrique and Lutz were childhood sweethearts who met while they were educated at independent schools in Bogota, Columbia, before moving to Australia in 2005.

A close friend told The City Paper in Bogota, "Maria Claudia had met her perfect match … and seemed very much in love before the children were born."

But the strains of bringing up two severely autistic children far from family were beginning to show, and they were reportedly on the verge of divorce.

Ms Lutz had told family that she was leaving the Northern Beaches and was returning to Colombia, but friends have remarked on how difficult she found it to travel with her two severely disabled children and how this limited her ability to leave.

Listen: Mamamia Out Loud discusses the tragic deaths. Post continues below. 

A close friend, told The City Paper that the marriage was strained with “constant worries of the future of their severely autistic children”.

“María Claudia wanted to return to Colombia,” she revealed.

But she said, “the children could not travel due to their health issues on a 14-hour flight and in order to comfort María Claudia, her family would visit Australia once-a-year.”

Maria Claudia Lutz appeared happy in the days before her death. Image: Facebook.

A Sydney based friend has said that Maris Lutz appeared happy in the days before her death.

Peta Rostirola told ABC's 7.30 that Ms Lutz had just finished a teaching degree and appeared "excited" after a meeting with a National Disability Insurance Scheme (NDIS) team.

Mrs Lutz spent Friday afternoon with Ms Rostirola, two days before she died, having coffee at a nursery.

"She'd had a meeting with the NDIS and she was so excited she was going to be getting all this help," Ms Rostirola said.

"She even felt guilty for taking that, she was just the most selfless person."

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