From Charlie Chaplin's autobiography, here is a straight-forward, heart-wrenching story from his life, on when he heard of his mother's waning mental health.

‘Your mother’s gone insane,’ said a little girl. The words were like a slap in the face. ‘What do you mean?’ I mumbled. ‘It’s true,’ said another. ‘She’s been knocking at all our doors, giving away pieces of coal, saying they were birthday presents for the children. You can ask my mother.’ Without hearing more, I ran up the pathway, through the open door of the house and leaped up the stairs and opened the door of our room. I stood a moment to catch my breath, intensely scrutinizing her. It was a summer’s afternoon and the atmosphere was close and oppressive.

Mother was sitting as usual at the window. She turned slowly and looked at me, her face pale and tormented. ‘Mother!’ I almost shouted. ‘What is it?’ she said listlessly. Then I ran and fell on my knees and buried my face in her lap, and burst into uncontrollable weeping. ‘There, there,’ she said gently, stroking my head. ‘What’s wrong?’ ‘You’re not well,’ I cried between sobs. She spoke reassuringly: ‘Of course I am.’ She seemed so vague, so preoccupied. ‘No! No! They say you’ve been going to all the houses and –’ I could not finish, but continued sobbing. ‘I was looking for Sydney,’ she said weakly; ‘they’re keeping him away from me.’ Then I knew that what the children had said was true.

‘Oh, Mummy, don’t talk like that! Don’t! Don’t!’ I sobbed. ‘Let me get you a doctor.’ She continued, stroking my head: ‘The McCarthys know where he is, and they’re keeping him away from me.’ ‘Mummy, please let me get a doctor,’ I cried. I got up and went towards the door. She looked after me with a pained expression. ‘Where are you going?’ ‘To get a doctor. I won’t be long.’ She never answered, but looked anxiously after me. Quickly I rushed downstairs to the landlady. ‘I’ve got to get a doctor at once, Mother’s not well!’ ‘We’ve already sent for him,’ the landlady said.

The parish doctor was old and grumpy and after hearing the landlady’s story, which was similar to that of the children, he made a perfunctory examination of Mother. ‘Insane. Send her to the infirmary,’ he said. The doctor wrote out a paper; besides other things it said she was suffering from malnutrition, which the doctor explained to me, saying that she was undernourished. ‘She’ll be better off and get proper food there,’ said the landlady by way of comforting me.

And on that note, let's see just how Chaplin's mother blamed him for her "insanity", all boiled down to...a cup of tea:

Although Sydney tried to cheer Mother up, telling her of his good fortune and the money he had made and his reason for having been away so long, she just sat listening and nodding, looking vague and preoccupied. I told her that she would soon get well. ‘Of course,’ she said dolefully, ‘if only you had given me a cup of tea that afternoon, I would have been all right.’ The doctor told Sydney afterwards that her mind was undoubtedly impaired by malnutrition, and that she required proper medical treatment, and that although she had lucid moments, it would be months before she completely recovered. But for days I was haunted by her remark: ‘If only you had given me a cup of tea I would have been all right.’

By the way, to say Chaplin was born into poverty is a huge understatement; please check this quote from the book:

I was well aware of the social stigma of our poverty. Even the poorest of children sat down to a home-cooked Sunday dinner. A roast at home meant respectability, a ritual that distinguished one poor class from another. Those who could not sit down to Sunday dinner at home were of the mendicant class, and we were that. Mother would send me to the nearest coffee-shop to buy a sixpenny dinner (meat and two vegetables). The shame of it – especially on Sunday! I would harry her for not preparing something at home, and she would vainly try to explain that cooking at home would cost twice as much.