84. Where one of several beneficiaries-(a) joins with the mutawalli in committing a breach of trust, or(b) knowingly gains any advantage therefrom without the consent of the other beneficiaries, or(c) becomes aware of a breach of trust committed or intended to be committed and either actually conceals it or does not, within a reasonable time, take proper steps to protect the interest of the other beneficiaries, or(d) has deceived the mutawalli and thereby induced him to commit a breach of trust, he shall be liable to compensate the other beneficiaries for any loss caused to them by such breach.