Personal representatives and trustees, whether heretofore or hereafter qualified or appointed, are hereby granted the power to donate a conservation easement as provided in the Virginia Conservation Easement Act (§ 10.1-1009 et seq.) or an open-space easement as provided in the Open-Space Land Act (§ 10.1-1700 et seq.) on any real property of their decedents and settlors, in order to obtain the benefit of the estate tax exclusion allowed under § 2031(c) of the Internal Revenue Code of 1986, as amended, provided they have the written consent of all of the heirs, beneficiaries, and devisees whose interests are affected thereby. Upon petition of the personal representative or trustee, the circuit court may give consent on behalf of any unborn, unascertained, or incapacitated heirs, beneficiaries, or devisees whose interests are affected thereby after determining that (i) the donation of the conservation easement will not adversely affect such heirs, beneficiaries, or devisees or (ii) it is more likely than not that such heirs, beneficiaries, or devisees would consent if they were before the court and capable of giving consent. A guardian ad litem shall be appointed to represent the interests of any unborn, unascertained, or incapacitated persons.