Ms Úna O'Malley feels she gets "absolutely no support or recognition" from the State for caring for her sister at home in Tallaght.
Her sister, Ms Marian Ennis (49), has cerebral palsy which includes a mental disability. Caring for her is a full-time job, Ms O'Malley says, yet she receives no payment from the State for doing this work.
She is not entitled to a carer's allowance because the State takes her husband's earnings into account. She strongly objects to the fact that the allowance - which is a maximum weekly payment of 139.60 - is means tested.
"What has my husband's P60 got to do with anything?" she says. "That would not be taken into account if I went out and got a job somewhere else so why should it count when I am doing this work?"
Marian has her good and bad days, her sister says. "Sometimes it's like looking after a three-year-old. Other days it's like looking after an eight-year-old, or maybe a teenager. Marian is able to get around, but you have to do a lot for her, like helping her when she has a bath."
Ms O'Malley does not receive regular visits from community care or mental health nurses. She was offered respite care in a centre on Old Bawn Road, but because it was an open house just across the busy road from her home, she feared that Marian could leave the centre at any time and attempt to go home.
Ms O'Malley believes all carers of mentally-disabled and elderly people should receive the carers' allowance.
"That's the one thing that would make life much easier. The money wouldn't be for me. It would be for Marian. I could buy her things and bring her on holiday," she says.
"If I didn't care for Marian, it would cost the Government a colossal amount of money but they cannot see that, or maybe they don't want to see it."
She does not feel that she needs daily nursing support now but says it won't be long before she needs professional back-up. "I'm 56 now and I know that in a few years we will need help. The years are flying by and I just won't be able to manage. "
