Delaware Code Title 30. State Taxes § 1163. Returns by fiduciaries

(1) Any deceased individual shall be made and filed by an executor, administrator or other person charged with the care of the decedent's property.  A joint or separate final return of a decedent shall be due when it would have been due if the decedent had not died;

(2) An individual who is unable to make a return by reason of minority, or other disability, shall be made and filed by a duly authorized agent, guardian, fiduciary or other person charged with the care of the individual's person or property, other than a receiver in possession of only a part of the individual's property;

(3) An estate or trust shall be made and filed by the fiduciary thereof;

(4) Two or more fiduciaries acting jointly, may be made by any 1 of them.