Sarah Pinheiro grew up in a house overtaken by junk. She says her childhood was neglected, that from a young age she was suicidal because her Mum's obsession with possessions drove every decision affecting her life. The family's four-bedroom Victorian home was overtaken by junk. Sarah is still haunted by the dark, worried about small spaces, of being surrounded, swallowed up, unable to escape. Asked about her earliest memories, Sarah doesn't recall a specific moment or event. She describes the things that were around her. Boxes everywhere, piled to the ceiling. Animal faeces. Clutter – clothes, newspapers, catalogues, rubbish. She lists the things she missed out on such as having friends visit and birthday parties at home. And the things that scared her – the sound of rodents eating as she slept, the prick of tetanus shots every time rusted metal or broken glass pierced her skin. The things that annoyed her – the smell of animal urine in the house, being hungry but unable to get into the kitchen. A dancer since she was young, Sarah has always been small. It's difficult to imagine rubbish stacked so high she was forced to suck in her elbows to avoid paper cuts walking down the hallway. And later, when there was only room to climb, the terror she must have felt when she slipped and fell between the boxes.

"This photo haunts me," says Sarah. "My soul was empty at this time. I felt nothing." "When I lived there you couldn't even see the back wall," says Sarah, of the kitchen in the house where she grew up. Sarah tried to stem the tide of junk her Mum brought home by smuggling it out in her backpack every morning and dumping it in the bin on the way to school. But it was pointless. When it got really bad, one of her brothers took the fly screen off his second-storey bedroom window and used a ladder to come and go. "You know something's wrong when your mother picks up five of every recipe card every time she goes to the supermarket but never cooks anything, and then you get in trouble for throwing one away," says Sarah.

Clinical psychologist and hoarding expert Chris Mogan says extreme hoarding, especially when it turns into squalor, can severely impact a child's psychosocial development. "For some people a little bit of hoarding doesn't interfere with their parenting, but for others there's neglect," Dr Mogan says. "You can get the impossible situation where you've got squalor where the appliances aren't working, where there's no cooking going on, the toilets are blocked, the animals are dominating the house." Mogan, of the Anxiety Clinic in Richmond, says children in hoarding households can be malnourished, bullied at school because of their appearance, and often fall behind in their studies. He has gone into many homes where the children have been removed. "These kids don't have friends visiting to play and they are not encouraged to go elsewhere so there's a real fortress mentality," he says. "In some situations children are going off to private school and coming home to bedrooms where they don't sleep on beds, but on newspapers on the floor." Dr Chris Mogan from The Anxiety Clinic. Credit:Jesse Marlow

In some cases it can be fatal. A five-year-old boy died in 2012 after cutting his foot on an opened can of cat food in his family's putrid Melbourne home. More commonly, the risks are associated with fire or falling objects. One of Sarah's brothers almost died when he was nine after catching rotavirus iglesia, a severe gastrointestinal disease normally contracted in third world countries. "He was drying out, his body shrivelled up like a sultana," Sarah recalls. "It was lucky one of the doctors at the hospital had seen it before." In Sarah's childhood home the family's pet dog, a poodle named Ebony who was blinded by her own matted hair, lived in the main bathroom. The other animals – 52 guinea pigs, three cats, chickens, rabbits, mice and rats – overran the house. If Sarah wanted a shower she would first have to climb over the junk that walled in her Mum's ensuite (her Mum eventually moved in there). Sarah's only escape was her local dance school, where she did classical ballet. She also loved scouts. For a while she lived next door with her grandmother, who taught her to knit. At one point she was removed for her own safety and put in foster care. What went on inside Sarah's suburban house was kept secret from the outside world. The children were warned to stay silent, visitors forbidden. Sarah, whose uniforms were always clean and ironed, showed no signs of the horror at home. She never even told her father about the hoarding, which started soon after her parents separated.

Former mental health worker Tania Reid, who specialises in helping hoarders, says children who grow up in these households often carry the burden alone. "There's the cliche that you see on Today Tonight where all the stuff is spilling out of the house onto the footpath, but this also occurs in secret in ordinary looking houses," says Reid, who has written a children's book on the topic. "Children either join in with the person who's hoarding because that's the only way to get their attention and their approval, or children will leave young." Tania Reid has written a children's book, Credit:Michael Clayton-Jones MCJ Sarah moved out for good at 16 and is estranged from her mother and two brothers. She finished high school by distance education and went on to study social work. The first half of her life trapped in that house still affects her sense of identity today.

"All of my childhood memories, most photographs, my birth certificate, my ballet and scout achievements, they're all gone," Sarah says. "That is something which should never and would never have happened if not for growing up there." And she has unanswered questions for those who were meant to step in when there was every sign of neglect at home. Why weren't questions asked by the health department when her brother was sick? Why did the police fail to chase up social workers on one of the many times they were called to the house? Why did child services not check in after her foster care placement ended? "Why did they all leave me there?" Sarah didn't return to her mother's house when she became homeless earlier this year, having being diagnosed with rheumatoid arthritis and unable to work and pay her rent. Instead, she bought a tent and lived in a caravan park on the outskirts of the city, got a job in a takeaway shop and saved up enough money for a new rental in Melbourne. Anything was better than going home. Her plan now is to become a children's counsellor specialising in helping young people who grow up in hoarding households. In her spare time Sarah knits stuffed toys the way her grandmother showed her and gives them away to friends' children. "If I could ever help anyone through this, I would," she says. "No child should have to live the way we did as children."