My mother added my sister and I to the deed of vacant land in 2002, making us joint owners with her and her husband. She died in 2003. Her husband died in 2016. In 2017, I bought my sister's share of the land, making me the sole owner. In 2018, less than a year later, I sold the land. How do I determine the basis of the land for capital gains purposes, and is it a short term or long term holding?
