Maryland Estates and Trusts Section 3-301
§ 3-301.
  (a)   A will may not be revoked by the subsequent birth, adoption, or legitimation of a child by the testator except under the circumstances referred to in § 4-105(3) of this article.
  (b)   A child described in subsection (a) or issue, if any, of such child who does not survive the testator, is entitled to a share in the estate to be determined and paid in accordance with § 3-302 and § 3-303, if:
    (1)   The will contains a legacy for a child of the testator but makes no provision for a person who becomes a child of the testator subsequent to the execution of the will;
    (2)   The child was born, adopted, or legitimated after the execution of the will;
    (3)   The child, or his issue, survive the testator; and
    (4)   The will does not expressly state that the child, or issue, should be omitted.