Brother and sister on Deed

[Lydia S.]

Hello all, If a brother and sister were deeded a home after the passing of their father, and the sister now wishes to buy out the brother (who has occupied the home for over 2 years), what is the process? Both parties are amenable. Is the brother exempt from paying tax on the buy-out since it's his primary residence? This is in Massachusetts, if that matters. Thanks for any comments!