News in 5: Questions after autistic boy escaped from carer and was killed; The royal baby is here; Masterchef contestant dies.

1. Questions after a boy with autism and a “zest for life” escaped from a care facility and was hit and killed by a train.

An 11-year-old severely autistic boy fatally struck by a train in Sydney’s south after running away from his carer has been described as a “beautiful angel”.

NSW Police mounted a large search involving the dog unit and Polair after the boy – identified by media as 11-year-old Alex Raichman – ran away at Oatley shops after 7pm on Sunday.

WATCH: An 11-year-old autistic boy escaped from a care facility, before being hit and killed by a train, from Ten News.

Alex, who was non-verbal, had been staying at a respite centre.

The whole community joined in the search for him, with resident Rosemary Sharpiro-Liu telling Seven News: “the whole of Oatley was on the street”.

“When I left home I said if that happened to my kid I’d want everyone out there and everyone was out there.”

He was found dead at Oatley train station about two hours after disappearing.

Civic Disability Services Limited confirmed the boy was in its care at a short-term accommodation facility when the incident happened.

The disability care service provider released a statement on Monday describing the boy’s death as “tragic and distressing”.

“This is a tragic and distressing incident and our deepest sympathies and thoughts go out to the child’s family,” chief executive Annie Doyle said.

Sydney Friendship Circle, a charity for families of children with special needs, on Sunday night desperately pleaded with the public on Facebook to find the boy.

Hours later the group shared the heartbreaking news about his death.

They described him as a “treasured son, grandson, brother and friend”.

“Today the world lost a beautiful angel. As we try to process this tremendous loss, your beautiful life flashes in front of us,” the group posted on social media on Monday.

“We are going to miss your mischievous smile, the joy in your eyes, your curiosity about the smallest creation and your zest for life.”

Flowers and tributes for the young boy were placed at Oatley station on Monday.

State Oatley MP Mark Coure said the incident was “just heartbreaking”.

“My heart goes out to the family, friends and carer this morning of an 11 year old boy who last night was found dead at Oatley Train Station,” Mr Coure wrote on Facebook on Monday.

“As a father, I can only imagine the grief of the family and extend my deepest sympathies for their unimaginable loss.”

Police are appealing for anyone who may have seen the boy to contact them. To donate money to help Alex’s family through this difficult time, click here.

2. The royal prince has arrived and he is Kate’s heaviest baby yet.

The new baby Prince of Cambridge has weighed in at eight pounds seven ounces (3.9 kilograms) - heavier than both Prince George and Princess Charlotte.

Charlotte, at eight pound three ounces, weighed slightly less than George's eight pound six ounces - but was still above average.

The average weight of a baby in the UK is around seven pounds seven ounces or 3.5 kilograms.

All of three of the Duchess of Cambridge's children have weighed more than eight pounds.

But the new prince is not the heaviest royal baby in recent years.

That title falls to Savannah Phillips - the daughter of the Queen's grandson Peter Phillips - who weighed eight pounds eight ounces in 2010.

George was the heaviest future king to be born in recent history.

Prince William weighed seven pounds five ounces in 1982, while Prince Charles weighed seven pound six ounces in 1948.

Prince Harry weighed six pound 14 ounces in 1984.

The Queen - then Princess Elizabeth - was born by Caesarean section in her maternal grandparents' London home and was also third in line to the throne at the time, but her weight was not announced, as was previously the custom for royal babies.

3. Tributes are flowing in for a MasterChef contestant in the UK who died while running the London Marathon on Sunday.

Celebrity chef in the UK Matt Campbell is dead after he collapsed while running the London Marathon on Sunday.

The 29-year-old, who appeared on the BBC program MasterChef: The Professionals, was running his second marathon in two weeks and was doing so to raise money for The Brathay Trust - an organisation that helps vulnerable people make positive changes in their lives, CNN reports.

Most importantly, he was doing it to honour the memory of his father, who died in 2016.

Shortly before the reace, Campbell posted to Instagram:

"Round two. Second marathon in two weeks, first Manchester Marathon and now London Marathon. I'm running in memory of my father for Brathay Challenges, thank you so much for this opportunity. Good luck everyone!"

It's reported he collapsed after running 36.2 kilometres of the 42.1-kilometre course, in what's been called "one of the hottest London Marathons ever". According to CNN, Campbell received immediate medical attention after collapsing but died later in hospital.

Tributes are flowing in for the young chef.

I’d normally be plugging my own justgiving page post-marathon, but that doesn’t feel right today. Matt Campbell’s page is already over £31,000 I will be donating in memory to him, please join me if you can. https://t.co/IebXuLlslW

— The Secret Marathon Runner (@marathon_secret) April 23, 2018

We are devastated by the news that our ex-student, Matt Campbell died while running the London Marathon yesterday. Matt was an incredibly talented, focused, and inspirational young chef and our deepest sympathies go out to his family & friends. pic.twitter.com/asS2bPPDD0

— Kendal College (@KendalCollege) April 23, 2018

It in no way softens the blow but it is at least heartening to see that since the terrible news of Matt Campbell's death yesterday broke, the sum raised on his just giving page has risen from the target of £2.5k to over £30k. https://t.co/ddtm7fcgky

— Jay Rayner (@jayrayner1) April 23, 2018

4. An Italian backpacker who removed women's underwear and filmed them while they slept is being deported.

A sexual deviant who touched and filmed the genitals of female backpackers while they slept or showered will be deported to Italy.

Alberto Dagrezio digitally raped, sexually assaulted or invaded the privacy of 44 women at two Brisbane hostels and other locations between February and December 2015.

The Brisbane District Court on Monday heard the 33-year-old deliberately targeted the Base and Bunk properties because he was familiar with their security systems.

He entered the venues late at night or in the early morning, left his shoes in common areas and pretended to be on his phone so it looked like he was a guest.

Dagrezio then located unlocked dorm rooms and went inside, where he looked for sleeping women who were semi-naked.

The Italian national pulled on their underwear so their genitals were exposed, before he filmed them.

By the time he was arrested his offending had escalated into the digital rapes of two women.

He also filmed female backpackers while they were showering.

A total of 36 women were targeted at the two hostels, while another eight were victimised at unknown locations across Brisbane.

Judge Paul Smith said one of the most disturbing elements of Dagrezio's offending was that some of the women didn't know they'd been assaulted.

"The ones who became aware of it would've been greatly affected by this," he said.

Judge Smith said Dagrezio had significant problems that included paraphilia, which is also known as sexual deviancy.

The court heard he had pre-existing "voyeuristic fantasies" that were fuelled by his interest in pornographic films.

"It manifested itself in Spring Hill when you started filming your female flatmates in the shower," Judge Smith said.

Dagrezio pleaded guilty to 66 offences including two of rape and nine of sexual assault in January.

Judge Smith said he took into account his early plea, but also had to consider the fact he could not release him on parole because his visa had been cancelled.

Dagrezio, who had already served more than two years' behind bars, was sentenced to five years' jail.

But it was suspended from Monday so he could be taken into immigration detention and deported to Italy.

The court heard Dazgrezio would receive psychological help when he returned home and would also likely be further investigated by Italian police.

5. WARNING: A man in NSW is inviting children into his car to "pet his dog".

Five children playing in a NSW park have been approached by a stranger who invited them into his car to pet his dog.

The children, aged between eight and 12, were playing in Morisset Park, Lake Macquarie, on Saturday afternoon when the man stopped his car next to the park and approached the children, inviting them into his vehicle.

The children declined and he left. A witness alerted police who want to speak to the man to clarify the circumstances.

He is described as being about 70 years old with short grey hair and wearing a dark-coloured long-sleeved shirt and reading glasses. He was driving a white Toyota Corolla with purple tinted windows. The dog was described as a small cream-coloured Chihuahua.

6. Australian teens are forgoing sleep for screen-time, leaving them at risk of developing depression and suicidal thoughts.

Australian teenagers are missing out on crucial sleep at great cost to their mental health, with screen time, caffeine and stress keeping them awake at night, warn public health experts.

Researchers at the Sleep Health Foundation were commissioned by VicHealth to conduct a 'rapid' research review exploring the links between sleep and mental wellbeing in adolescents.

On average adolescents get between six-and-a-half to seven-and-a-half hours of sleep on school nights, according to the study released on Tuesday.

This is well under the recommended eight to 10 hours of sleep per night for a person aged 14 to 17 years.

Concerningly, the findings found not getting enough sleep during this important stage of growth and development was linked to suicidal thoughts in teens.

"Not getting enough sleep can really mess with all of us but young people in particular are at risk of a range of mental health issues such as depression, anxiety, low self-esteem and mood issues," said VicHealth CEO Jerril Rechter.

"Sleep problems during childhood and as a teenager can lead to depression later in life. Sadly poor sleep is also associated with suicidal thoughts in teenagers so it's really critical we support young people to get the sleep they need."

Insomnia and Delayed Sleep-Wake Phase Disorder (DSWPD) were also common sleep problems reported among this age group.

A survey of adolescents in Adelaide showed two-thirds (66 per cent) reported at least one symptom of a sleep disorder, such as insomnia.

The study also confirmed too much time spent on screen-based technology was largely to blame for the widespread lack of sleep.

Caffeine and stress caused by greater homework loads were other common behavioural and environmental factors, said Sleep Health Foundation Chair Professor Dorothy Bruck.

"The stereotype of a lazy teenager who sleeps all day is actually an anomaly - teens need more sleep than older people yet we know most of them aren't getting enough," Professor Bruck said.

The good news is there are simple things that teens and their parents can do to promote more sleep, including being active during the day and no "scrolling through social media" just before bed, said Professor Bruck.

The research showed teenagers who stopped using their phones just one hour before bedtime gained one hour and 45 minutes of extra sleep over a school week.

Tips for Promoting Sleep

* Set a regular bedtime and wake up time

* Try to relax before bed - mindfulness activities like meditation or gentle yoga may help

* Avoid stimulants in the evening like coffee, tea, soft drinks and energy drinks

* Set up a comfortable sleep environment

* Try to switch off screens an hour before bed - instead read a book or listen to music

* Get active during the day

* Try to spend time together as a family in the evening