Client purchased parent’s home with siblings about twenty years ago.  Due to family circumstances at the time, the three kids decided to buy out one parent (50%) interest in the home.  The resulting transaction was that one parent would still have ownership of 50% and the three kids would have a 1/6 interest in the property.  Fast forward twenty years, the remaining parent (with 50% interest) have now passed on and with skyrocketing home values, children have all decided to sell the property at a significant gain.  As there were no estate tax planning during the preceding years and no consideration of gifting property interest, etc., I wanted to get some insight on the resulting tax consequences.  There would be capital gains based on the basis when the property was acquired by children compared to current sale price; however would that now be capital gains based on a 1/3 ownership interest and how should measurement date for basis be best determined (based on acquisition of initial interest, parent 50% FMV interest at time of death, etc.)?