As I see it sasu you could move out of your sister's house and rent somewhere yourself, leaving space for your mother, or you could rent somewhere big enough for you and your mother, or you could extend and adapt you sister's house so there is room for you all and ground floor facilities for your mum. I do wonder if you can afford to pay for her travel from Colombia why can't you afford to house her?
To obliterate your address on packaging
Kate Garroway-Care at home costs
Water Pollution -“ A National Disgrace”? A case for renationalisation?