Anne always knew her boys were different. Years later, a diagnosis left her crushed by guilt.

Cairns mum Anne Russell had never even held a baby in her arms until her first son was born. But from the very beginning, instinct told her there was something different about her boy.

As a child, Mick, now 37, was a tiny baby who cried non-stop, for months. He was developmentally delayed and while his temperament grew calmer by his teen years, he was hamstrung by physical issues: he had epilepsy, his teeth didn’t grow properly, he had a tumour on his jaw, and he was far smaller than any of his peers.

Ms Russell’s concerns were intensified after the birth of Mick’s little brother Seth three years later.

“He was a big strapping boy, and his behaviour was off the planet,” she told Mamamia. “It didn’t make sense.”

Seth had violent psychotic episodes, he left school at age 14 after a number of suspensions, he had attempted to take his own life several times, and he couldn’t hold down a part-time job – usually because he would do something so bewildering, like stealing scratch-its from the news agency.

Ms Russell, 63, felt helpless. Her sons weren’t responding to any of the traditional parenting strategies she and her husband Don tried to implement.

“I was constantly failing at everything. I can’t describe the feeling of failure and chronic stress. I couldn’t take them to the supermarket, to friends’ places. I was isolated,” she said.

Physically and emotionally, the two boys were opposite. But they had one key thing in common: they both couldn't comprehend boundaries and consequences.

She said her doctors had brushed off her concerns. Seth had previously been diagnosed with ADHD, but Ms Russell was certain it was something else.

Ms Russell began doing some research and stumbled upon Foetal Alcohol Spectrum Disorder (FASD), a lifelong condition relating to permanent brain damage caused by mothers drinking alcohol during pregnancy. Ms Russell drank during her two pregnancies and said she was unaware of the risks because she had never been properly educated on the dangers by anyone, including her doctors.

When carrying her firstborn, she said she had the odd drink every now and again. Then, during the second pregnancy, she was averaging about three drinks, three times per week.

She said reading the symptoms of FASD hit her "like a bolt of lightning".

It wasn't until both boys were on the cusp of adulthood, when Seth was 17 and Mick was 20, that they were formerly diagnosed with FASD by a doctor in the USA.

However, finally confirming this fact didn't make the diagnosis any less devastating; the guilt was crushing.

"I deep down knew they had it before the diagnosis, but once they were diagnosed, that was it. I couldn't go back. I couldn't pretend it was something else like I dearly wanted to," Ms Russell said.

"It took a long time before I told my husband and told the boys. The guilt is horrendous and never leaves.

"Because not only do (parents of children with FASD) have to worry about the child they brought into the world, but also the damage can last up to five generations."

While the emotional anguish is something she and her sons will have to live with for the rest of her life, the diagnosis helped empower her to - at long last - support her children in the way they needed: with a lot of rules and routine. She now knew for certain that their anti-social actions were not behaviours, they were symptoms.

As Ms Russell looks back on old photos of her sons - men she describes as "just the best people" - she feels shaken.

"I had so many hopes for them, and had no idea that anything could take that away. I especially didn’t have a clue that their fate had already been set in concrete. They were both such happy kids," she said.

"If only I hadn’t bothered with alcohol at that time in my life but honestly I was a pretty messed up person."

Ms Russell became driven to turn her family's struggle into a positive, and in 2007 she founded the Russell Family Foetal Alcohol Disorders Association to help others and to raise awareness in the broader community.

"FASD can take a happy, apparently stable child and turn him into a suicidal, drug addicted, violent and psychotic teenager," she said.

"It's terrible for parents who don't know why their children are behaving the way they are. And hundreds of thousands of people in Australia are going through that."

Because FASD is so under-recognised and undiagnosed in Australia - and shockingly, is still not acknowledged officially as a disability - its prevalence is equally hard to determine.

National Organisation for Foetal Alcohol Spectrum Disorders (NOFASD) executive officer Louise Gray told Mamamia the condition was estimated to affect anywhere between 1-8 per cent of Australia's population.

On a global level, research published last year in the journal JAMA Paediatrics - which included Australian studies - found that one in every 100 children worldwide suffered from FASD, and that one in every 13 women who drank alcohol while pregnant would have a baby with FASD.

Brisbane mum Tricia* comes at the issue from a different angle. She and her long-term partner Olivia* had been foster carers for many years. Then one day, they took in a sprightly toddler who was diagnosed with FASD.

Tricia and Olivia didn't know what exactly the condition was, but they saw straight away that Patrick*, at age three-and-a-half, was not like the other kids.

He only knew about 10 words, he wasn't toilet trained, he was hyperactive and impulsive, and he would have violent meltdowns triggered by exasperation or confusion. He also had a tiny body with excessive muscle tone (at age five he looked like a three-year-old) - a condition named hypotonia.

"He was a pretty complicated little guy... He just stood out in so many different ways,” she said. “As a toddler he could pull himself on top of bench tops and door frames.”

But Tricia and Olivia decided they were in it for the long-haul, prepared to give him the tightly controlled and routine home environment Patrick, now aged 17, needed to thrive. Eventually, they became his legal guardians, and Patrick grew into an affectionate and fun young man.

"We fell in love with him and we could see how frustrated he was and how he couldn't explain to us what it was that was going on. He was so stuck.... We felt like we could give him what he needed."

Tricia stressed she'd never felt anger towards Patrick's birth mother, but said she deeply resented how hard his life had been.

She said that one of the more heart-wrenching realities of Patrick's life was that, to this day, the parents of other children continued to try to exclude him from social activities.

"He doesn't look like a kid with a disability so people treat him as if he is rude, disobedient, a delinquent, without having any understanding that he has brain injuries... and we are constantly judged as being bad parents," she said.

"He never got invited to parties in primary schools. He never had any friends, he's never been included. His behaviours have improved enormously through a huge amount of work, and yet he's still copping it. What more can we do?"

Adulthood is set to be Patrick's biggest challenge yet. Tricia said Patrick loved school and wanted to work, but like many children with FASD, she feared he didn't have the literacy or numeracy skills to pass Year 12, go into further education and find an understanding employer.

As FASD is also not recognised as a standalone disability, it doesn't attract the same funding and support as other more well-known conditions.

NOFASD's Louise Gray said she believed there were two reasons there was an ongoing lack of awareness of FASD.

Firstly, she said Australian society was reluctant to address the problem because alcohol was so central to our culture, meaning the industry and consumers didn't want to accept its harms.

Ms Gray said official health guidelines were also at times unclear, causing people to mistakenly think the odd drink during pregnancy wouldn't hurt their unborn baby.

The Australian Institute of Health and Welfare reported that in 2013, almost half of pregnant women reported consuming alcohol during their pregnancy. What's more, around 45 per cent of pregnancies are said to be unplanned - meaning women could be unknowingly harming their unborn babies.

She said it was crucial for couples to understand that anyone who was pregnant, was planning a pregnancy or could be pregnant, abstained from alcohol. (Increasing evidence suggests the same goes for men.)

"There is no safe time and no safe amount and no safe type of alcohol during pregnancy," she said.

LISTEN: How to talk to children about disability. Post continues after audio.

The second key reason for the poor awareness of FASD was the fact that its effects on patients could be so varied, Ms Gray said.

According to Ms Gray, health professionals in Australia were not adequately equipped with knowledge of how FASD displayed in patients, meaning many children were slipping under the radar.

She said the complexity and variety of FASD symptoms made if difficult to diagnose, compared to most disabilities which had a clear pattern. Sufferers of FASD were often wrongly diagnosed with autism or ADHD.

But she emphasised the huge difference an accurate diagnosis made for families. She said too many parents in Australia had been left puzzled by their children's behaviours, whereas if they knew they had FASD, they would understand their learning challenges and how to seek the appropriate support.

"The biggest problem is that their symptoms get mistaken for bad behaviour, without understanding that underlying brain damage is causing it," she said.

The symptoms of FASD can vary widely, because the impacts are determined by the timing, frequency and quantity of alcohol consumed over the course of a nine-month pregnancy, but there are a few core symptoms:

• developmental delays and learning disabilities, including difficulties with litearacy and numeracy
• an inability to control and regulate emotions
• an inability to learn from mistakes and predict consequences
• exposure to alcohol during earlier pregnancy is believed to be linked to phyiscal abnormalities including below-average height and weight, narrower eyes, a thin upper lip and little to no groove between the nose and lips

As well as these direct mental and physical symptoms, people with FASD are more likely to fail at school, be suicidal, be vulnerable to addiction issues and be caught in the criminal justice system.

One vital thing that Ms Russell and Tricia agree on is that while their sons can be challenging, they are loving and wonderful people. None of this is their fault, and they are loved to bits by their parents. They just wish the public- and the healthcare system - had the awareness to deal with this.

"Don't judge a book by its cover. People are so much more complex. Before making assumptions about my son and the man he is, scratch just an inch below the surface," Tricia urged.

FASD is a messy disability tangled with emotion because the cause is an uncomfortable one to accept. But the biggest danger is that the disorder becomes easier for the public to ignore than to address.

Experts agree that acknowledging FASD as a serious problem does not mean blaming women for intentionally harming their babies. It only means one thing: educating the public on the risks of drinking during pregnancy, and bringing affected mothers and children the support they so desperately need.

If you need support, please visit the Russell Family Foetal Alcohol Disorders Association. You can also visit the National Organisation for Foetal Alcohol Spectrum Disorders or call their helpline on 1300 306 238.

You can follow Sophie Aubrey on Twitter.