Neb. Rev. Stat. § 25-21,152: Fiduciary or interested person; action to declare rights.

Any person interested as or through an executor, administrator, trustee, guardian, or other fiduciary, creditor, devisee, legatee, heir, next of kin, or cestui que trust, in the administration of a trust or the estate of a decedent, an infant, person with a mental disorder, or insolvent, may have a declaration of rights or legal relation in respect thereto:

(a) To ascertain any class of creditors, devisees, legatees, heirs, next of kin, or others; or

(b) To direct the executors, administrators, or trustees to do or abstain from doing any particular act in their fiduciary capacity; or

(c) To determine any question arising in the administration of the estate or trust, including questions of construction of wills and other writings.