Sally's son was 20 days old when he received a life-threatening diagnosis: Cystic fibrosis.

The morning of our baby’s diagnosis started like any other Wednesday with a newborn; in utter chaos. My husband Matt left for work early and I scrambled to breastfeed, shower, get some assemblage of breakfast together and drive my toddler and pre-schooler to their different care arrangements looking presentable, on time and with lunch.

However my phone was ringing incessantly and once I found it in the cavernous cave of my baby bag, I was alarmed to find eight missed calls from the paediatricians rooms asking me to come in that afternoon. I instantly knew something was dangerously wrong with the tiny baby I clutched to my chest when the paediatrician asked me where my husband was.

Even when, a few years before, a scan had revealed the tiny heartbeat of one of the babies I had carried for the first trimester could not be found, no-one had ever asked for my husband to be present.

When I arrived, I looked at the doctor, and saw his eyes were sympathetic and kind. This filled me with dread.

“Where is your husband right now. Is he in the city? He needs to be here for the news I am about to tell you,” he said.

The phrase blood running cold actually doesn’t do the feeling I had justice. Instead it was like a doctor taking an enormous vial of liquid nitrogen and inserting the icy mixture into my carotid artery, rendering my blood, my entire body, completely frozen.

At this point, my youngest child Harry was 20 days old. I was still in the midst of that warm, woolly haze of new love and sleep deprivation.

For the rest of that time in the doctor’s surgery I experienced an out-of-body situation and looked down on the unfolding horror show. The paediatrician looked at the woman that was me and said calmly, “I have the results for your baby’s heel prick test. Can you please call your husband and ask him to come here straight away?”

I called Matt, and spent the eight minutes it took him to arrive on Google looking into the heel prick test. The first entry said the heel prick tested for several rare but serious genetic conditions, of which cystic fibrosis is the most common. Being completely unaware of the other genetic conditions it tested, I repeated over and over in my head: please don’t let it be cystic fibrosis, please don’t let it be cystic fibrosis. Please let it be something else, just don’t let it be cystic fibrosis. I knew very little about the disease except that it caused lung issues, and that you died of it… young.

In that small, drab paediatrician’s room within an office building in North Sydney, my worst fears were revealed: the paediatrician revealed that Harry had the ‘life limiting’ condition of cystic fibrosis.

My first instinct, probably like any parents thrown down the rabbit hole of a new diagnosis, was that there must be some mistake. They must have the wrong baby. We had previously had two healthy children and had no family history of this chronic condition, they must have simply got it wrong.

I was told politely that the newborn screening was unlikely to have generated incorrect results.

The Heel Prick Test, designed by Robert Guthrie in the 1960s, checks for CF by looking for elevated levels of a pancreatic enzyme with the fancy name trypsinogen in that tiny smear of blood.

When my baby’s test came back as being in the top 10 per cent of results, the screening then looked for a specific gene in the blood sample, and my baby was found to have homogenous copies of the Delta F 508 gene. This meant my baby had inherited one CF gene from me, and one from my husband.

Once my husband arrived he took control of the situation, asking intelligent questions about whether our baby would be able to go to school (yes), and day-care (no), whether our other children could have it (not likely), whether he would have a mental disability (no), whether he would be able to live a ‘normal’ life (yes, but with a lot of time in hospital).

The next day we met with the Dr Sandra Chuang who would become Harry’s main doctor and lifeline at Sydney Children’s Hospital, Randwick, who sat down with Matt and me for more than three hours, talking about cystic fibrosis in an incredibly positive way, and taking time to answer all our questions.

We learnt one in 25 Australians are carriers of the gene causing CF, and one in 2,500 babies are born with the condition in Australia. At Sydney Children’s Hospital, Randwick they currently treat 180 children, although many more children are seen in New South Wales at Westmead and in Newcastle.

Harry and I then met with Dr Chuang every Wednesday at the CF clinic for the next six weeks, and she spent hours answering my questions and monitoring Harry’s growth and breathing.

Because cystic fibrosis affects multiple organs, our baby has a team of specialists monitoring his health. As well as Sandra, he has a gastroenterologist, dietician, physiotherapist, a clinical nurse consultant, social worker and a psychologist. The initial learning period can be likened to scaling Denali naked, without food or oxygen, however because of our child’s amazing medical team we felt incredibly supported.

We learnt cystic fibrosis mainly causes problems with the lungs and the digestive system. The lungs are affected as the cystic fibrosis transmembrane regulator creates a thick, sticky mucous that causes inflammation and also creates the perfect breeding ground for bacteria.

Physio is needed daily to keep the mucous in the lungs moving so that bacteria aren’t able to breed as easily. Medical teams now treat any bacterial infection incredibly seriously and it is not uncommon for CFers to be on antibiotics for the whole of winter, as well as antibiotics intravenously to treat an acute bacterial infection.

To a mum of a child with CF, germs are the enemy, and any sneeze in the direction of your baby could render them in hospital, so it is important to avoid people who are sick and coughing.

With regards to the digestive system, Harry has pancreatic insufficiency because enzymes aren’t able to travel through the sticky mucous from the pancreas to the stomach. He simply can’t absorb fat. Similarly to a diabetic having to keep a close eye on their insulin, a person with cystic fibrosis who has pancreatic insufficiency will have to take enzymes every time they eat food containing fat.

On top of CF, our baby had gastroesophageal reflux disease (GORD) and a severe intolerance to cow’s milk and soy protein, meaning I had to eradicate all dairy and soy products from my diet if I wanted to breastfeed.

Harry screamed relentlessly – day and night – only stopping for short periods when he was asleep. The miniscule amounts of dairy and soy remaining in my breastmilk even after I had eliminated it from my diet caused my baby to bleed internally, and it was strongly suggested to me by his team of medical experts that I stop breastfeeding.

He had failure to thrive, and if he didn’t put on weight the following week he would need to be admitted to hospital to be tube fed.

But I was trapped in a cycle of confusion and anxiety and ruminating thoughts about being a terrible mother. I breastfed my other children. I would be a failure if I didn’t breastfeed him. How could I NOT breastfeed him when I had already given him CF? But he isn’t putting on weight and his doctors are telling me I should give it up.

Thankfully my great friend Jess, who was a triage nurse at a major Sydney hospital, saw what was going on and went out and bought me a delicious dairy milk coffee. Because of Harry’s food intolerances, if I drank the coffee, breastfeeding would be over. She could tell by looking at Harry that he was dangerously ill and that I wasn’t capable of making a rational decision. And she simply didn’t take no for an answer.

I drank the coffee and I will be forever thankful to her for stepping in and taking charge on our behalf.

We switched Harry to an amino-acid-based formula and he started to put on weight, slept a bit more and screamed a lot less.

Coming to terms with my delicious newborn having a chronic genetic condition that affected every single cell in his body wasn’t easy. I spent a lot of days feeling numb and in shock, and nights on social media scrolling through the worst kinds of images of people with the condition.

I read somewhere a diagnosis can be likened to grief where you mourn for the healthy child you have lost. I was familiar with grief and I didn’t feel a loss for the child I might have had, but I was paralysed by an immense fear of the future and I wanted to run away from a situation where a child of mine might die from a condition they had inherited from me.

I loved my son beyond comprehension however there was a niggling feeling that I wasn’t the best mother for him.

The lowest ebb of Harry’s diagnosis came around four months after that fateful day in the paediatrician's room. My husband was away and my middle child, aged two, had fallen from a ledge in our garden, had hit her head badly and had been unconscious and unresponsive for ten minutes.

I called an ambulance, and when they arrived and assessed her they called for a second ambulance as she required a critical response unit. Thankfully, after 12 hours in hospital our toddler was ok and just had a concussion, but a few days after when I arrived in the hospital carpark for my regular appointment at the CF clinic, the stress of the premature birth, CF diagnosis and dealing with the trauma of my toddler’s fall came to a head.

I sat in the hospital carpark and suddenly thought: “I can’t do this anymore.”

I told anyone who listened that I wasn’t coping and the reaction in the hospital was swift and effective. They worked with my GP and a local psychologist to give me the support I needed.

A 2014 US study found close to two in every five mothers’ of children with cystic fibrosis suffered from depression, and an even higher proportion from anxiety. A US TIDES study found a direct link between a child with CF suffering from depression if their parent did. What is so frightening about this, is that if a person with CF suffers from depression, they are five times more likely to die within a five-year period than another CFer. In short, I had to prioritise my own health to look after the health of my children.

To get through this period I changed my behaviour and started to be kinder to myself. Instead of crying all the way to the hospital I called a friend Sar who would always make me laugh by telling me ridiculously bad jokes.

Whenever someone offered to help I unequivocally said yes. Including when my sister hired me a fabulous babysitter who we all adore. I spent individual time with my other children who weren’t sick and watched them form a close bond with the brother they love.

Every child with CF has a completely different experience. Our first year was problematic, and Harry ended up having three surgeries, four hospital admissions and spent some time in ICU. However his second year has been much better - he hasn’t had any hospital admissions and has managed to stay well.

Heartbreakingly, the average life expectancy of a person living with cystic fibrosis is currently 37, and much younger in nations without the incredible access to world class medicine we have in Australia.

Harry’s doctors have reminded us that we need to think of the life expectancy of 37 for people who were born 37 years ago. These children didn’t have access to the huge advances gene modifying therapies that have come into play in the last ten years. Some drugs have been put on the PBS recently that will improve the lives of older people with CF, and much better drugs Harry will benefit from are currently in stage four trials in the US.

His doctors believe, as long as there are some major breakthroughs and as long as we remain vigilant in terms of keeping him well, not missing medications and physio, that Harry will live to old age.

5 things I have learnt from a difficult diagnosis:

1. Be kind to yourself
2. Say yes to anyone who offers to help
3. Tell doctors (and anyone) if you aren’t coping
4. Trust doctors, not Google
5. It is a marathon not a sprint, and you can’t do it on your own.

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