Parents love their children through thick and thin, but it's a feeling that isn't always reciprocated.
These are the children who killed their parents through shocking acts of selfishness and betrayal.
Sarah Marie Johnson was just like any other 16-year-old girl living in Bellevue, Idaho.
The high school student adored her dad Alan, 46, but would often fight with her mum Diane, 52.
Despite this, both her parents always wanted what was best for their little girl.
When Sarah started dating Bruno Santos, 19, a rift grew between her and her parents.
Bruno had a history of drugs and violence, and when they became aware of this, Diane and Alan told her to break off the relationship.
But she disobeyed and instead, spent the night at Bruno's.
When Alan discovered this, he turned up at the front door and demanded that Bruno stay away from Sarah or he'd contact the police about his shady past.
He then took his daughter home and grounded her.
But Sarah was fed up with her parents' interference.
So at 6am the next day, she opened her dad's gun case and pulled out a rifle.
Then she crept into her parents' room while her mum was asleep and dad was showering.
First, she aimed the rifle at her mother's head and pulled the trigger.
The shot alerted Alan and he rushed out of the bathroom in a bathrobe.
He saw his dead wife in the bed and then spotted Sarah holding a gun.
He begged her not to fire, but she shot her dad in the chest and he died.
Sarah then ran over to a neighbour's acting distressed and they called 911.
When police investigated, they found a bloody pink bathrobe and a latex glove with gunshot residue in a bin outside the house that contained Alan, Diane and Sarah's DNA, implicating her in the crime.
She was found guilty of murder and was jailed for two life sentences.
The Gilbert family were renowned for their self-made financial success in New York City.
Thomas Gilbert Sr, 70, ran a successful hedge fund.
He lived with his daughter and wife Shelley, while his son Thomas Gilbert Jr lived in his own apartment nearby.
Unlike his father, Thomas Jr struggled to hold down a steady job and had known very few successes outside of surfing.
He suffered with depression, anxiety, paranoia and obsessive compulsive disorder, and despite taking medication, his parents desperately wished for him to seek professional help.
They agreed to cut their son's allowance in an effort to force him to seek psychiatric help.
But instead of complying, Thomas Jr bought a gun via Facebook.
When he turned up at his parents' house for a visit, his mum Shelley hoped it was a sign of good news.
Thomas Jr told her to leave him alone with his dad, so they could 'talk about business'.
She left the room but became worried after putting her ear to the door and hearing silence.
She found her husband on his back, his hand covering a gun on his chest, placed there in a clumsy attempt at a staged suicide.
Thomas Jr was found guilty of second-degree murder and two counts of criminal possession of a weapon.
When dinner was served in the Chapman household, son Daniel, 22, told his parents he couldn't come to the table because he was in the middle of a computer game.
Frustrated dad, Stephen, 56, told his son to look for somewhere else to rent the next day.
He then stormed into the family's office in their Sydney home and turned off the internet modem.
Afterwards, he went into Daniel's room and tried to remove the cables from the computer.
But Daniel, who collected medieval weapons as a hobby, picked up a hunting knife from under his bed and stabbed his dad in the back.
After removing the 14cm blade, he went to see his mum, Elaine.
"I stabbed him," he told her coldly.
Elaine tried to call an ambulance but accidentally dialled 999, the British emergency number, where she is originally from.
Ten minutes later, a neighbour reported the stabbing.
Three ambulances arrived, but Stephen died from blood loss.
Daniel Chapman pleaded guilty to manslaughter and was jailed for at least three years, noting his autism spectrum disorder and his "momentary lapse" in being unable to control himself.
When swimming pool worker Martin Ruddy, 29, was struggling with nearly $10,000 debt, his marriage started falling apart.
So he went to his dad Eric, 64, for help.
Martin was close to his dad and mum Carol, 53, and was always running errands for the family.
But his mum had been left disabled by a stroke, and dad Eric, from Newcastle, UK, was ploughing all of his savings into ensuring Carol would be looked after if he ever passed away.
So when debt-ridden Martin went to his father for the cash to pay out his debts, he refused.
Furious, Martin hit him with a brick.
He then used a serrated knife to cut Eric's face to make it look like he'd been attacked by a burglar.
Despite being drugged by Martin with antidepressants, his mum, who was disabled, tried to dial emergency services. When Martin caught her, he strangled her with a TV cable.
He then inflicted injuries on himself with a brick and scissors to look like he'd fallen victim to the attack, too.
He stumbled to the next door neighbour's and claimed they'd all been attacked by intruders.
Andrea Hardy followed him back to the house where they tried to resuscitate Eric and Carol.
They were taken to a nearby hospital where they were pronounced dead.
Martin was later found guilty of murdering his parents and jailed for 35 years.
When police responded to a disturbance in a home in Delmar, New York, they discovered court clerk Peter Porco, 52, in a pool of his own blood, dead from head injuries.
His wife Joan was lying next to their bed with similar head trauma.
Her face was disfigured, one eye was destroyed and her skull was caved in.
Despite this, she was still alive.
Near her was a bloodied axe.
As paramedics lifted Joan onto a gurney, a detective asked if she could tell him about her attacker.
"Was it a family member?" he asked and she nodded.
He questioned if it was her oldest son Jonathan, but she shook her head.
Then he asked about her younger son Christopher and she nodded.
Joan soon slipped into a coma, but her answers firmly placed Christopher as the focal point of the investigation.
When officers started digging, they discovered he was more than 350km away, studying at the University of Rochester.
Nonetheless, officers found tensions between the Porcos and their son, particularly when it came to money.
Christopher owed money on his new Jeep Wrangler and his university tuition. He took out a loan to pay his fees, forging his father's signature on the debt.
Two weeks before Peter was murdered, he even confronted his son about the money and in an email threatened to report him.
But he'd remained a loving dad.
"We may be disappointed with you, but your mother and I still love you and care about your future," Peter had added.
Eventually, Joan emerged from her coma to discover her husband was dead and her face was seriously disfigured.
Still, she believed that Christopher had nothing to do with her husband's murder and denied identifying him.
But evidence suggested that Christopher did make the 350km journey back home on the night of the murder, with a toll collector remembering his yellow Wrangler passing by.
He was eventually found guilty of one count of second-degree murder and one of attempted murder.
He was sentenced to 50 years to life for each count.
For an entire week teenager Tyler Hadley had been telling friends he was throwing a party at his parents' house while they were out of town for the weekend.
Many of his mates didn't believe him since his dad, Blake, 54, and mum, Mary-Jo, 47, had been increasingly strict with him for the past few months.
But when Saturday arrived, Tyler, 17, posted on Facebook.
Party at my crib tonight… maybe.
Eight hours later, he posted on Facebook again saying that the party was on.
A concerned friend asked about the chances of his parents coming home.
They won't, trust me, Tyler responded.
Soon, more than 60 teens had piled into the Hadley home in Port St Lucie, Florida, most of whom were strangers to Tyler.
They lounged on the couches, played beer pong and chain-smoked cigarettes.
When friends asked Tyler where his parents had gone, he told each one a different story.
As the night went on, he became more reflective.
He told one guest he'd done something bad, and if caught he'd go away for 'a long time'.
By around 1am, he confided in his friend Michael."I killed my parents," he told him.
Michael didn't believe it, so Tyler led him to the master bedroom, where there were traces of blood on the door.
He unlocked it and Michael spotted a pile of blood-soaked towels, and underneath, a thick white leg.
Tyler explained to Michael what had happened.
Shortly before 5pm, he'd hid his parents' phones so they couldn't call for help.
He took three pills of ecstasy, listened to a song to psych himself up and then found a claw hammer in the garage.
He stood behind his mum while she worked at the computer before he raised the claw end of the hammer and brought it down on her head.
When she screamed, Tyler's dad ran out of the master bedroom and nothing could have prepared him for what he saw."Why?" he repeated as Tyler turned on his dad and beat him to death, too.
When it was over, he wrapped his parents in towels and dragged their corpses to the master bedroom.
Then, he started the clean-up. It took Tyler three hours to hide the incriminating evidence in the bedroom with the bodies.
Then he took a shower.
Michael was in shock listening to the story.
Meanwhile, the other teens at the party got word that another shindig was being thrown nearby, so they clambered into their cars and tore away.
But the noise was too much for one neighbour who called the police.
When officers arrived, there were less than 20 people still at the party.
Tyler opened the door and spoke to them for a few minutes before they left.
By 4am, everyone had gone, leaving Tyler alone in the house.
But Michael, who'd seen the bodies, called Crime Stoppers the moment he left, and the police returned to the house.
Tyler Hadley was arrested and later convicted of murdering his parents.
He was sentenced to life in prison.