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Не совсем понял вначале. Мне кажется, что в начале должно быть My friend Cathy's family и далее как есть. You can talk to her and say that there's nothing wrong with buying things from charity shops. She should feel free to use this option as long as her family is in need. Once they find better jobs and make some more money on their own, they are going to stand on their own two feet and be independent. You can tell her that buying things from charity or as they're also called "thrift shops" help charity organisations raise money to help homeless people and children with health problems. I'd call it "killing two birds with one stone".