Assume a trust that was initially for the benefit of its settlor (who is now dead) has the following additional terms: All net trust-accounting income to settlor’s surviving spouse (X) for life; trustee may invade principal for X’s health, maintenance and support; upon X’s death, the trust corpus is to be distributed outright and free of trust to X’s children, who are currently minors. X is the sole trustee. X also possesses an express, implied, or constructive right/power to invade principal for X’s personal benefit without court review or the appointment of a guardian ad litem. It is a common misconception that such a trust would have terminated by operation of law at the death of the settlor, all interests having “merged” outright and free of trust in X. Here is why there is no merger: The existence of the children’s contingent equitable quasi-remainders, evanescent though they may be, prevents termination by merger of all legal and equitable interests. Or, to put it another way, the existence of an express, implied, or constructive general inter vivos power of appointment in and of itself, whether the power is of the fiduciary or non-fiduciary variety, will not trigger a merger in the powerholder. See National Shawmut Bank of Boston v. Joy, 53 N.E.2d 113 (1944) (“And where an estate is given over in default of appointment, the nature of the estate of the remaindermen is not affected by the power of disposition until that power is exercised.”). The conflation of power of appointment doctrine and merger doctrine in the trust context is taken up in Loring and Rounds: A Trustee’s Handbook §8.7 (merger) [page 1041 of the 2015 ed.].The text of §8.7 is reproduced in its entirety below.