Family ties … the author as a baby with his parents, Rhonda and Michael. Enmore was a rough neighbourhood back then. Drug and alcohol abuse was common, and I'd often hear huge fights as I lay awake at night. I remember being scared a lot. I slept with an axe next to my bed after being threatened for not paying enough protection money to a local gang. Mum loved trains, and it's something I inherited from her. Mum had limited capacity to navigate public transport, so I would memorise timetables and maps and get us somewhere for a day trip. The best memories I have from my childhood are of Mum and I catching the train to Newcastle or the Blue Mountains for a day trip, and having some hot chips or a pie before returning home. Mostly, though, we'd end up at Aunty Marilyn's house in Penrith. Marilyn took care of me in ways my own mum couldn't. She'd cook meals and take me shopping with her own two kids. I'd play backyard cricket with my cousins or watch the Panthers play at Penrith Stadium. When Marilyn passed away from cancer in 2007, I lost the closest thing I'd ever had in my life to a traditional "mother" role. I was always sad to return home from Aunt Marilyn's house after a weekend or school holidays. Reality always hit pretty fast. Dealing with Mum's psychotic episodes and trying to keep her to a schedule of psychiatrist appointments and visits from nurses and social workers took its toll.

My dad lived reasonably close by, in another block of public-housing flats in Glebe. Sometimes he'd try to help, but Mum would scream at him and he'd give up. He did come over every day after school, though, to cook dinner and push me to do my homework. But this changed after he had a severe heart attack and quintuple bypass. It took him years to recover, and he couldn't visit as much as he used to. One of my earliest memories is the first day of kindergarten. Well, it was the first day for me. The term was already two weeks in by the time Mum dropped me down to the local school, Camdenville Public. The other kids thought it was pretty strange that I walked in during the middle of the day some weeks late. Lots of them started teasing me about Mum. Christmas was always tough. Not because we went without - there were plenty of charities willing to help with gifts and a Christmas lunch. My problem was the shame I felt at accepting their charity. My father had drummed a strong sense of pride into me. He was a strong man, managing to get by on meagre social-support payments, while saving enough to pay for after-school tutoring during my high school years. Mum was on one side of the door, we were on the other, trying to talk her into taking her medication - she'd become convinced it was killing her.

My mother never wasted money, either. She'd often say, "I don't smoke. I don't drink. I don't gamble." In her own way, she helped me get a good education. From the time I was born she would tell people that I was going to Fort Street, a selective high school in nearby Petersham. Eventually, as a result of my dad coming over and making me do my homework, I was accepted into Fort Street just as Mum had predicted. During my high school years I tried to project the image of being a normal teenager, but found it increasingly hard. My diet was terrible. I often skipped breakfast, ate hash browns or a pie from the canteen for lunch every day, and had KFC or a slice of pizza for dinner. My teeth were a mess; I had bleeding gums. I didn't get my driver's licence until a few years ago and I only recently learnt to swim. I was never late for school, though - it was much better than being at home. I knew education was the way out of the poverty cycle. I completed year 12 at Fort Street and was offered a scholarship to the University of NSW to study economics and accounting. After my first year I worked full-time throughout my degree, but continued to live at home. When I was 22, I finally made the decision to leave home. I was working 15- to 16-hour days and needed to find a share house closer to the office to make it easier to balance work, study and my volunteer work - I was helping to set up the Australian Youth Climate Coalition alongside a young climate campaigner named Anna Rose (to whom I'm now married). Mum was angry when I told her I'd be moving out to live a few suburbs away, around the corner from Anna's place. One of the unfortunate features of Mum's mental ill health is her tendency to invent dramatic stories when she needs more attention. One day, just before I was offered the role of national director of GetUp!, I was visiting Mum when I found a letter. Strangely, it was summonsing me for a court appearance. I asked Mum what it was about; she said she didn't know. So I walked down the road to the police station, where the officer checked the file and told me that while I was at work Mum had walked into the station and claimed that her son hit her. I went back home and talked to Mum - she apologised and went back to the station to tell them she'd made it up. But nothing could be done, a date was set and the case was heard during my first week at GetUp!.

It was thrown out of court in just a few minutes. But it was an awful experience that reminded me I'd have to spend more time with Mum, even though I wasn't living at home any more. Anna and I visited regularly. Mum was taking her medication and for a while things seemed to be calm. But in 2011, her health started to deteriorate rapidly. The timing couldn't have been worse. Anna and I had just got engaged. We'd just bought our first home and were planning our wedding. Ironically, much of my work time with GetUp! was being spent on mental-health campaigning. Eventually, the campaign won $2.2 billion in new mental health funding, but it felt like I was fighting a war on two fronts. Mum couldn't live by herself any more, that was obvious. She was refusing to take her medication and, in states of psychosis, locking the door to her flat. Her doctors recommended one of the last resorts available to families: a control order that would allow police to forcibly enter her flat and take her to hospital, where she would be medicated. I drew the line. No matter what, I wasn't willing to have Mum go through that trauma. So Anna and I spent hours outside her block of flats. Mum was on one side of the door, we were on the other, trying to talk her into taking her medication - she'd become convinced it was killing her. Eventually, after she managed to get through the worst of it and back on to stable medication, we found Mum a place in supported accommodation. Even though I felt uncomfortable about it, I asked for advice from the experts I'd been working with on the mental-health campaign. The group home was great for Mum. But over the course of the next year and after a few more unexpected hospital visits, her doctors recommended a higher level of medically supervised care. We found a place at a larger aged-care facility in the same neighbourhood, and Mum moved there at the end of last year.

Being a carer is a difficult experience for any child. Many children don't have the things that made it easier for me - a caring aunt, a father who kept me mostly out of trouble, and support from social workers and medical professionals. As my caring role continues, I'm also lucky enough to have an incredibly supportive wife. I owe a lot to my dad. We are closer now than when I was in high school. These days I see him about once a month, and he's helping out with my ACT Senate campaign. Growing up the way I did meant I learnt to be self-sufficient and to navigate systems to achieve the best outcomes. I learnt how to read people - to be alert to the smallest signs of a changing mood - and to diffuse tense situations. I saw first-hand the inequality that exists in our society. It breaks my heart that this inequality is worsening. I also learnt not to judge people by first impressions. As Atticus Finch says in To Kill a Mockingbird, "You never really understand a person until you consider things from his point of view - until you climb into his skin and walk around in it." Seeing life from my mum's point of view is difficult. Things you and I take for granted - like how to take the bus, prepare a meal, or have a normal conversation - are confronting and overwhelming for her. There's a lot she doesn't understand. So much of her world takes place in her head. But there's more to her than just her ill-health. She likes music from the '50s, and she still likes trains. I think she's proud of me, and she gets excited when she sees me on TV. And she knows - I hope - that I love her and that I'll always be there for her.