Try this , delete her details then put the laptop as close as possible to your aunts router , this will lock it with the strongest possible signal. Now go back home and try again. Who is your isp , I am with bt , if you can register your home as a wi fi hot spot you will legally be able to use other peoples set ups that have also got themselves registered as a hot spot. That's the trade off , you use theres and somebody else uses yours. You might even find a stronger signal than your aunts.
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