Under Massachusetts real estate license law, a broker must disclose any personal interest, or the interest of an immediate family member, in a transaction to all parties. This is a matter of fiduciary duty and is explicitly required under 254 CMR 3.00.

Failing to disclose that the seller is the broker’s cousin constitutes a conflict of interest and violates the duty of loyalty, disclosure, and honesty to the client (the buyer). While it is not illegal to buy or sell property involving relatives, the relationship must always be made known to avoid misrepresentation or concealment of material facts.

Therefore, the broker is in violation because the familial relationship was not disclosed.