§ 10-6.7 Exercise by all donees; exceptions

Whenever a power of appointment, other than a power in a trustee to
invade trust principal under section 10-6.6 of this article or under the
terms of the dispositive instrument, is created in two or more donees,
all must unite in its exercise, unless the instrument creating such
power provides otherwise. But, if before its execution, one or more of
such donees dies or becomes incompetent, such power may be exercised by
the survivor or the competent donee, unless such exercise is explicitly
barred by the terms of the instrument creating such power.