The attorney represents the trustee, not the trust. Yes, the attorney would defend the trustee and the attorney would be paid from the trust assets. The attorney would advise the trustee and make sure that the trustee properly administers the trust, to the extent possible.
Some of these duties are to give proper notice to the beneficiaries, to file any necessary paperwork with the court, to file ta returns, to advise the trustee with respect to management of the assets and distributions to beneficiaries.
This is a gross simplification, as there could be 50 different duties, depending on the situation. Acting as trustee is something you would seldom want to do without an attorney's assistance.
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