Parents are meant to love and protect their children, not kill them.

This time last week Sofina Nikat was laughing and cuddling with her 14-month-old daughter.

She was changing her nappy and cleaning up the food spills on the floor. She was softly kissing her and taking giggling, giddy videos.

An adoring mother, a calculating killer? Right now we just don’t know.

This time last week Sofina Nikat's daughter was alive. Image via Facebook.

We don’t know what torment was going through her mind, we don’t what she was doing. We don’t know – aside from a police report of a confession – how or why her daughter Sanaya Sahib died.

But we do know that once again as a nation, as parents, we have been shocked by the death of a child allegedly at the hands of the person who should love them the most.

We do know that if Sofina Nikat is guilty of her daughter's murder that she joins a growing list of parents who have committed filicide. A list that appalls and shocks us and yet at the very same time leaves us wanting to understand it.

Because most of us - me and you - can't fathom just how a parent can kill their own.

Matthew Neil and Kim Smart's newborn died after they and an all night drinking session. Image via Facebook.

Last week we were taken aback by the tale of two British parents who escaped charges after they got so drunk in an all night booze binge that they lost track of their newborn baby and he died after being found squashed between the wall and his two-year-old brother’s bed.

We stopped and wondered how can parents care so little?

Through neglect, through addiction, through mental illness we tried to reason their actions.

We did the same when a mother in Cairns  stabbed seven of her own children and her niece and when an 11-year old girl was stabbed to death by her mother in Brisbane.

And then a father drove his car off a wharf in South Australia after stopping at McDonalds for a coffee. In the back were strapped his two boys, shot dead by him moments before.

Collectively the nation shook its head and cried out for the violence to stop.

Damien Little drove his car off a wharf in South Australia. Image via Seven News.

These actions are impossible to fathom, let alone come to terms with.

If the allegations against Sofina Nikat are proven true they are chilling. A video of the young mother posing and cuddling with her 14-month-old taken just two days before the murder shows no inkling of her alleged intentions, and leaves us with more and more soul searching.

What kind of society are we that one of us could murder their own baby daughter?

It’s a difficult question to tackle.

Parents give children life, they don’t take it away. Parents are meant to protect, nurture, care and teach their children. Not harm them and certainly not kill them.

Didn’t she as a mother feel overwhelmed by a primeval, fierce dedication to keep her child safe? What happened to that silent vow each of us made to our newborns into their downy, soft scalp to keep them safe, to protect them no matter what?

A childhood friend of Sofina Nikat posted a tribute to Sanaya Sahib on his Facebook page asking the very question on the lips of every parent in Australia this week “What happened?”

He wrote: “Sofina Nikat what went wrong that you took this step. You loved her alot [sic] most of us knew this. You had been a great friend since I knew u back from early high school But Why???.."

Luke Batty's father killed him while Luke was at cricket practise. Image supplied

As hard as it is to believe, a roll call of names shows us that something, somewhere goes wrong in a parent’s love.

Names like Luke Batty, Jai, Bailey and Tyler Farquharson, Savannah and Indianna Mihayo, River and Nyobi Hinder, Koda and baby Hunter Little and Sanaya Sahib

These are just a few of the victims we have come to know over the past decade who have been killed at the hands of a parent.

It can be either parent – mother or father – who kills their child but far more fathers kill their own children than mothers do. Six out of every ten children in filicide (the deliberate act of a parent killing their child) are killed by their fathers.

In the US 450 children are killed every year by their parents. In Australia, the number is smaller – around 27 a year, but between 2002 and 2012 this adds up to 238 children killed by their parent or parents.

In a submission to the Royal Commission into Family Violence, the Filicide Research Project wrote that boys were more likely to be killed than girls, the most likely methods including drowning, asphyxiation, assault, knifing, smoke inhalation from a fire, drug overdose and withholding prescribed medication.

Fairfax Media reports that the most common stress factors that led to filicide were mental illness and partner separation

"In the Victorian study only one third of perpetrators gave an explanation and these were mostly unclear, with 'I lost control' being the most frequent one expressed," the submission said.

Studies have shown that murders by mothers are “altruistic” — they murder out of love, not out of hate, with a genuine belief that they are doing the children “a favour”.

Fathers get painted with a darker brush. They murder out of revenge a lot of the time.

We ask why? Image via Facebook and Seven News.

Jack Levin, an American criminologist, told USA Today that mothers who murder tend to kill their newborns on impulse. “The day a child is born is the day a child is most likely to be killed by a parent,” he says.

But for fathers it is different – planned, often meticulous. They are more likely to kill the entire family, then themselves.

“A man sees himself as the main support of a family,” forensic psychiatrist Phillip Resnick told USA Today, “He may feel like it is his responsibility to not let his family suffer. You may have a severely depressed father who may think his children are better off dead with him.”

And yet despite expert after expert attempting to explain it to us over and over, we are appalled and confused by these cases.

Darcey Freeman was thrown off a bridge by her father. Image supplied.

When sentencing Arthur Freeman, the father who threw his four-year-old daughter Darcey off Melbourne’s Westgate Bridge in 2009, Justice Paul Coghlan put words to our disbelief:

“You brought the broader community into this case in a way that has been rarely, if ever, seen before. It offends our collective conscience,” he said.

It doesn’t just offend, it also sickens and breaks us.

The awful awful truth is, it will happen again. It is another dark reality of the inexplicable toll family violence takes.

If this post brings up any issues for you in relation to family violence, or if you just feel like you need to speak to someone, please call 1800 RESPECT (1800 737 732) – the national sexual assault, domestic and family violence counselling service. It doesn’t matter where you live, they will take your call and, if need be, refer you to a service closer to home.

If this post brings up issues for you in relation to suicide, or you just need someone to talk to, please call Lifeline on 131 114.