This discussion explores whether a relative, specifically a daughter and son-in-law, can use a member's society flat for Chartered Accountancy practice, even though they are not members themselves. Legal precedents suggest that CA practice is a profession, not business, and can be permitted in residential premises up to 50% of the space, provided it's not the dominant use. However, the relative is considered a third party, and permission from the society's managing committee and adherence to bylaws are crucial, especially if the original member is relocating.