Mom died in 2006. I was placed as power of attorney for my Dad's financials. He died in 2013. I need to request final monies from his investments, insurance, death benefits, etc. so that I can split it with my Sister as he has requested in his will. I was told before I could do that I needed a tax I'd for his estate. Plus I was told after his death my POA is no longer valid. Is that all correct?