looking for legal answers please

[niece]

Can you help to unravel this problem. My Uncle has died leaving his elderly sister (in Nursing home after severe stroke) Also leaving a son (also in a nursing home as he is mentally disabled). The only other living blood relatives to my uncle are my brother and myself. Although I must add that two grand children by another son who was not married and has been dead for a number of years, but bore these two children have suddenly appeared from nowhere. Anyway, it has come to my attention in the last few days, that my brother's wife has power of attorny over my uncles finances as she also does over my aunts finances. He left a house and money(I have no idea how much) The proceeds from the house are now in my sister-in-laws hands as I suppose is the money, jewellry, contents of the house etc. I am told that my uncles will left everything to my sister-in-law on the understanding that my aunt and my uncles son never want for anything in their lifetime. My question at this time, (although I have many running around in my mind) is what happens to the capital in my sister-in-laws account upon the death of my aunt and my cousin.???(neither of whom are compus mentos enough to make a will of their own) Can I ask to see a copy of this will???? I know that my aunt has god children whom she would wish to leave something to in the event of her death.